51 Percent Attack Simulation On Proof Of Work Blockchain — Complete Documentation & Simulation

Overview & System Context

51 Percent Attack Simulation On Proof Of Work Blockchain: Comprehensive Web-Sourced Technical Investigation Exhaustive Research Dossier · Pure Web-Scraped Content: ~8658 Words · Real Software Screenshots: 3 1. Executive Overview & Technical Background Video game modding (from "modifying") is the process of player and fan-authored alteration of a video game and is a sub-discipline of general modding. A set of modifications, called a mod, can either alter an existing game or add user-generated content. Modders, people who mod video games, can introduce a variety of changes to games, including altering graphics, fixing bugs, and adding unique gameplay elements. Mod development uses official or user-made software development kits, distinguishing it from in-game creations. Modding a game can also be understood as the act of seeking and installing mods to the player's game. People can become fans of specific mods and can involve themselves in the process of mod development and discourse. In cases where modding is popular, players use the term vanilla to describe the unmodified game (e.g. "Vanilla Minecraft"). Mods that extensively transform gameplay are known as total conversions, with some developing into distinct games. As early as the 1980s, video game mods have also been used for the sole purpose of creating art, as opposed to a playable game, leading to the rise of artistic video game modification, as well as machinima and the demoscene. With tens of thousands of mods created for popular games, the proliferation of video game modding has made it an increasingly important factor in the success of many games. Modding extends the replay value and interest of the game.

A specific date of origin for video game modding has not been agreed upon by historians, partly due to discussion over what constitutes a mod and partly because of insufficient historical documentation. However, the very first computer games already were being actively modified by the first generation of hackers, and researchers have described modding as an evolution of the hacker culture which pioneered the video game industry.

Widely considered one of the first computer games, the 1962 game Spacewar! was distributed freely as testing software for the PDP-1, an early computer. The game was a result of hardware and software experimentation, supported by the programming culture at the Massachusetts Institute of Technology (MIT). On university campuses where the computer was installed, programmers continued to experiment with the game by modifying it heavily, allured by the prospect of fixing a "dire problem [...] as easily as changing a few instructions", as Steven Levy describes. Their efforts resulted in a wave of improvements to Spacewar!, from changing aspects such as gameplay physics to creating new graphics. The final version of the game was ultimately a product of a group effort of hackers, who contributed to the game without pay. In this way, Spacewar! was not only the first video game, but also the first video game to be modded. On the popularity of hacking Spacewar!, Levy reflected:Like any other program, it was placed in the drawer for anyone to access, look at, and rewrite as they saw fit. The group effort that stage by stage had improved the program could have stood for an argument for the Hacker Ethic: an urge to get inside the workings of the thing and make it better had led to measurable improvement. And of course it was all a huge amount of fun.Other early video games also released as iterations of collaborative improvements. Colossal Cave Adventure, a text adventure game developed by Will Crowther and released in 1976, was greatly expanded upon by Stanford graduate Don Woods. After receiving the source code to the game from Crowther, Woods increased the game's complexity and released a modified version in 1977 to instant success. The desire to improve software—the "hacker ethic", as described by Levy—became a crucial factor to the emergence of modern modding culture. Before the development of affordable and more accessible personal computers, the ability to mod games was restricted to where computers at the time were able to be installed, such as university campuses like MIT. With the advent of home computers in the late 1970s to early 1980s, such as the Apple II and the Commodore 64, video games were given a new space to flourish, accompanied by a new generation of modders. The subculture of "cracking" video games—hacking their source code—emerged as a niche endeavor among hobbyists. Cracks added gameplay cheats or removed copyright structures, allowing games to be distributed freely.

Using basic file editing software and a program that would dump the contents of files, modders additionally scoured games for their assets through trial and error, with the goal of replacing them with their own levels and graphics. A famous example is Castle Smurfenstein, a modification of the 1981 Apple II game Castle Wolfenstein. Andrew Johnson and Preston Nevins, two high school students, replaced the game's Nazi characters with those from the popular 1980s cartoon The Smurfs. The game is often cited as a pioneering example of modding culture.

As video games grew more sophisticated, hacking them became an increasingly cumbersome task, often requiring modders to effectively write over the original content. While modders created amateur game editing tools out of necessity, they were often buggy, inefficient, and incomplete, ultimately necessitating good programming skills for mod development. New assets were processed through multiple software packages in order to be modded into the game engine. Scott Miller, founder of 3D Realms (formerly Apogee Software), was fascinated by the levels and level editors fans created for Apogee's 1991 game Duke Nukem, reflecting: "We just didn't expect players to take the time and effort to create their own development tools." Modding continued with the release of Wolfenstein 3D in 1992, published by Apogee and developed by id Software, who had bought the rights to Castle Wolfenstein. Miller and his team at Apogee noted how modding helped extend the life of the game by providing free additional content for players. One such mod swapped the game's music with the theme song from the children's show Barney & Friends and replaced the final boss with Barney the Dinosaur. While some members of id were concerned about copyright infringement, id programmers and co-founders John Carmack and John Romero were delighted by the Barney mod. Carmack was surprised by its sophistication compared to the Apple II cheats he had created for games such as the Ultima series in the 1980s. Intrigued, he made a conscious effort to facilitate custom content creation when designing the company's next game, Doom. Released in 1993, Doom was the first game to introduce modding to a wider audience due to the degree of depth it allowed its modders. With Wolfenstein 3D, players had to erase game data to replace it; this destructiveness concerned Carmack and Romero. When developing Doom, Carmack purposely separated the game engine files from other assets, including level architecture, graphics, and audio, which were stored in a "WAD" file (an acronym for "where's all the data?"). While the system was also motivated by the game industry's push towards realism that required larger storage, it was specifically intended to make modding easier. With Doom, modders only needed to change which WAD file the game would reference, meaning that custom assets could be modified and distributed without sharing the original game data.

Figure 1: Application Binary Interface And Why It Matters To Understand ... Nearing the official release of Doom, Carmack sent emails to Wolfenstein modders, detailing the game's new modding capabilities. He also uploaded the source code for the game's level editing and utilities programs. Weeks after the release, hackers developed level and map-editing programs to modify existing Doom levels or make other minor adjustments. In 1994, the Doom Editor Utility was created by an international team of modders led by a student at the University of Canterbury, greatly lowering the skill threshold required to make a mod and advertising the ability to create entirely new levels. The DeHackEd from a University of Michigan student was released in the same year, which additionally allowed users to modify the executable file of the game. Later, in 1997, id published Doom as open source, allowing a greater customization of mods with the source code available. The open nature of Doom inspired a flood of creativity, with modding tools promising to "do almost anything to any level". Another factor in the popularity of Doom modding was the increasing popularity of the Internet and the advent of the World Wide Web, which allowed modding communities to form. Using online forums, modders were able to pool their knowledge and findings for the game. At a time when the video game industry guarded their intellectual property through copyrights and patents, id Software's willingness to share details about their game's files was novel. Companies like Atari had sued modders in the past for copyright infringement, including a pair of MIT students who had sold modded circuitry intended for the Atari arcade game Missile Command. The release of the source code for Doom's editing software caused debate amongst the team at id, with Carmack's actions being supported by Romero. In exchange for the technical foundation for modding, id requested that mods should only work with the retail version of the game and not the shareware version, benefiting the company commercially. Later first-person shooter developers, such as Valve and Epic, consistently include level editing tools with their games, and it is common for role-playing and strategy games to make a level editor available. By encouraging player-driven content, id created channels for entry into the video game industry for Doom's modding community.

Final Doom, released by id in 1996, integrated fan-made levels, with a share of the profits going to the modders involved. In 1995, id hired Tim Willits as the first employee from the Doom modding community, who later became studio director of id's parent company ZeniMax Media. 2. System Architecture & Core Working Principles After the success of Doom, id software would release their future games as open source. Mods for id's Quake, such as "Capture the Flag" and "Team Fortress", became standard gamemodes in later games in the shooter genre. In addition to first-person shooters, which are popular games to mod, the virtual pet genre, with games such as Petz and Creatures, fosters younger modders, particularly girls. Valve used WorldCraft, a fan-produced tool for Quake, to design Half-Life. In addition to its single-player campaign, Half-Life included the rudimentary multiplayer modes deathmatch and team deathmatch, a game mode created by John Romero for Doom. The multiplayer mods Day of Defeat and Counter-Strike became popular, and eventually Valve acquired them, giving them an official release. With the increase in popularity of the modding scene, video game companies began to capitalize on the appeal of creating user-generated content. By the mid-1990s, PC games were commonly bundled with modding tools, external software which allows users to create mods for their paired games. Games that launched with these tools were noteworthy in review and often contributed to their commercial success; in 2003, eight of the top 10 selling PC video games were bundled with modding tools. Steam, a video game digital distribution service created by Valve Corporation, was specifically designed for the proliferation of successful, stand-alone mods. The platform offered a US$995 licensing fee plus royalty for modders to distribute their games. With a beta release in 2002, Steam included a retail-version of Day of Defeat, originally a total conversion mod for Valve's Half-Life whose rights were purchased by the company. Gabe Newell, the founder of Valve, noted that his perception of video games shifted from viewing them as entertainment to embracing them as "productivity platforms". Since then, the client has become one of the largest online marketplaces for games. The platform introduced full support for finding and playing mods for Valve's Team Fortress 2, a game that itself originated as a mod for Quake. The Steam Workshop, introduced to the platform in 2012, allows players to mod Steam-hosted games directly within the interface.

Websites for hosting and sharing mods are widely used by the modding community. ModDB was founded in 2002, with over 300 million mod downloads as of 2025. Since its inception in 2001, Nexus Mods has become one of the largest modding websites; as of 2024, the website has over 47 million members and hosts a total of 539,682 mod files, developed by 128,361 mod authors. The website accrued a lifetime total of 10 billion mod downloads for 2,683 games the same year. Other websites are dedicated to the modding scenes of specific games. Large mod teams often host their own websites to showcase the development of their mods. These websites feature detailed database and advanced search functionality that allow users to easily find mods for their games, becoming social centers for modders and their shared knowledge. Additionally, video-hosting websites, blogs, and official game discussion forums provide channels for users to discuss and discover mods. Free content delivery tools, known as "mod managers", are available to streamline the mod installation process and aid players who are less technically literate. These tools manage downloads, updates, and mod installation. Steam offers the Steam Workshop within the game launcher itself, allowing a users to share mods for simplified download and installation in supported games.

Game developers also create official mod managers either alongside their games, such as the Paradox Launcher for games created by Paradox Interactive, or within the games themselves, such as in Baldur's Gate 3. Copyright law relating to video games and mods is an evolving legal issue. Uncertainty revolves around which party is legally the copyright owner of the mods—the company that produced the game, the creators of the individual mods, or the player that installed the mods. Under current law, mods are viewed as derivative works, as they are based upon or incorporate part of the original game and are developed by a third-party without a license. In US copyright law, different statutes cover various aspects of video games, such as graphics, audio, and source code. Most pertinent is the Copyright Act of 1976 (17 U.S.C. § 102), which protects "pictorial, graphic, and sculptural works", "sound recordings", and "literary works", among others. In past cases, mods have been viewed as derivative works not classifiable under fair use, and they are violations of the copyright holder's consent if developed without permission. Additionally, the mechanisms of how the modder accesses video game source code may violate the US Digital Millennium Copyright Act, through circumvention of technological measures intended to prevent the game from being copied. Mods are "presumptively illegal" when they breach a game's end-user license agreement (EULA) and terms of service (TOS), as is prohibited under the Computer Fraud and Abuse Act. Despite the lack of legal protection, modding continues to thrive due to encouragement from video game developers, who make moddable games. The companies' willingness to allow modification of their property is typically outlined in the game's legal contracts, including its EULA and TOS. Companies that wish to encourage modding often include terms that grant them ownership over any user-generated content (UGC) created for their games. An example is Electronic Arts (EA), who qualifies modding for their games, such as The Sims 4, according to their EULA from 2022: "When you contribute UGC, you grant to EA […] sublicensable license to use, host, store, reproduce, modify, create derivative works, publicly perform, publicly display or otherwise transmit and communicate the UGC". Other companies discourage modding through aggressive litigation in addition to strict legal contracts. In the 1998 case Micro Star v. FormGen Inc., the courts granted FormGen, the publisher of Duke Nukem 3D, a preliminary injunction against Micro Star, who packaged user-made level mods for the game and sold it as Nuke It. FormGen had stipulated in its license for the game that player-made levels must be offered for free. Modding poses a threat to artistic control that may lead game companies to pursue litigation against mod developers. In 2009, Square Enix sent a cease and desist letter to mod developers that used art from a ROM file of their game Chrono Trigger, threatening "up to $150,000 damages per work". Additionally, companies may take legal action against mods for multiplayer games which could impact fairness. Square Enix sent another cease and desist in 2025 to a developer whose mod allowed other players to view each other's modded characters in the online game Final Fantasy XIV. Officially, mods are against the TOS of the game, with game producer Naoki Yoshida arguing that such mods "negatively impact the core game, its services, [and] intended game design". Another concern is the use of copyrighted material owned by another company, such as a mod for Quake themed around Alien vs. Predator which was legally contested by 20th Century Fox. At least one modder received legal action from Mattel for the unauthorised use of the character Thomas the Tank Engine in a The Elder Scrolls V: Skyrim mod. Some modders regard the use of copyrighted material in mods to be part of a "moral economy", often settling on a system of shared ownership, where mods and code are freely shared with the common good in mind. "Moral ownership" over games they play leads modders to appropriate proprietary material and ignore copyright altogether. It has been argued that total conversion mods may be covered in the United States under the concept of fair use. Modding can be compared to the open-source-software movement and open-source video game development. In 2006, Second Life generated interest from its focus of user-generated content (mods) and how intellectual property rights to this content remained with the creator. Second Life players are able to sell these items in an in-game market. Literature on user-generated content in video games in the context of UK and European copyright law is limited. Scholarship mostly concerns the liabilities of intermediaries who provide this content rather than creators themselves. The UK National Crime Agency reported that modding can act as a pathway to cybercrime. In 2015, members from GTAForums, a Grand Theft Auto fan site, reported instances of malware being circulated through mods written for Grand Theft Auto V. Two of the mods in question, "Angry Planes" and "No Clip", came with malicious code for loading a remote access tool and a keylogger for stealing Facebook and Steam account credentials.

A total conversion is a mod of an existing game that extensively removes aspects of the original game, including art, characters, plot, and music, and replaces it with new assets that run on the game's engine. Total conversions can result in a completely different genre from the original. Examples of famous total conversions include Counter-Strike, whose developers were hired by Valve to create a standalone version, Defense of the Ancients, which was the first MOBA to have sponsored tournaments, and Garry's Mod, for which fans created thousands of game modes over its decade-long development. The Half-Life modding community splintered across the different total conversions available, often modding for a particular total conversion rather than Half-Life in general. Equestria at War, a total conversion mod based on the animated television series My Little Pony: Friendship Is Magic, is a popular mod of Hearts of Iron IV, placing seventh in the players' vote for Mod DB's 2023 Mod of the Year awards. Many popular total conversions are later turned into standalone games, replacing any remaining original assets to allow for commercial sale without copyright infringement. Some of these mods are even approved for sale while using the IP of the original game, such as Black Mesa. League of Legends and Dota 2 were both originally mods for Warcraft III: Reign of Chaos. Due to the increasing complexity of games, the amount and quality of total conversion mods has decreased. Modders also blame a lack of resources, the remote chances of profit (due to EULAs prohibiting the sale of mods), and the likelihood of a takedown notice from game companies as significant barriers to entry.

Figure 2: Blockchain And Cybersecurity Overview Of Blockchain 51 Percent Attack ... An unofficial patch is a mod of an existing game that fixes bugs in a game or unlocks content normally inaccessible in official gameplay. Unofficial patches can reveal cut content from released games, whose files can be left in the game's code. An example is the Hot Coffee mod for Grand Theft Auto: San Andreas, which unlocks a sexually explicit minigame not accessible in the game's original release but left in its code. As a result of the mod, the ESRB changed the rating of the game from Mature (M) to Adults Only (AO). In the fourth quarter of 2005, Rockstar released a "clean" version of the game with the "Hot Coffee" scenes removed, and the rating of the game was reverted to Mature. In May 2006, a similar event occurred with The Elder Scrolls IV: Oblivion.

3. Software Implementation, Frameworks & Protocols This is a list of several significant scientific events that occurred or were scheduled to occur in 2021. 1 July Construction begins on the Square Kilometre Array, with first light planned for 2027. In the debate about the cognitive impacts of smartphones and digital technology a group reports that, contrary to widespread belief, scientific evidence doesn't show that these technologies harm biological cognitive abilities and that they instead only change predominant ways of cognition – such as a reduced need to remember facts or conduct mathematical calculations by pen and paper outside contemporary schools. However, some activities – like reading novels – that require long attention spans and don't feature ongoing rewarding stimulation may become more challenging in general. A study finds that ~9.4% of global deaths between 2000 and 2019 – ~5 million annually – can be attributed to extreme temperature with cold-related ones making up the larger share and decreasing and heat-related ones making up ~0.91 % and increasing. 2 July The first scientific review in the professional academic literature about global plastic pollution in general finds that the rational response to the "global threat" would be "reductions in consumption of virgin plastic materials, along with internationally coordinated strategies for waste management" – such as banning export of plastic waste unless it leads to better recycling – and describes the state of knowledge about "poorly reversible" impacts. Researchers report that a mix of microorganisms from cow stomachs could break down three types of plastics. Scientists identify GPR75 variants as alleles protective against obesity in ~640,000 sequenced exomes. 5 July Scientists report the discovery of a bone carving, one of the world's oldest works of art, made by Neanderthals about 51,000 years ago. A scientific review summarizes evidence from nutrition research for diets for atherosclerosis prevention. 7 July A preprint finds the SARS-CoV-2 Delta variant to cause a ~108 % increased – or more than twice as large – risk for hospitalization, a ~234 % increase for ICU admission and 132% for death compared to non-VOC variants. Researchers present a programmable quantum simulator that can operate with 256 qubits. 8 July – Scientists report that in the past – with little relevance to future evolution – lower temperatures were associated with larger Homo body sizes and that long-term variability in precipitation was correlated with brain size.

10 July – Scientists report in a preprint the discovery of long extrachromosomal DNA structures, they call borgs, which appear to incorporate genes from organisms they encounter. These structures, which could turn out to be an unknown form of giant viruses or "giant linear plasmids", co-occur with a species of archaeon which may host them, shares many of their genes, whose main chromosome is only three times larger and whose capacity for anaerobic oxidation of methane as well as other biological functions – such as production of proteins – the borgs may augment. 12 July – Scientists report in a preprint that the viral load in the first positive test of infections with the SARS-CoV-2 Delta variant was on average ~1000 times higher than with compared infections during 2020. 14 July Researchers report finding the earliest known fossil life on Earth, in the form of "putative filamentous microfossils", possibly of methanogens and/or methanotrophs, that lived about 3.42-billion-year-old in "a paleo-subseafloor hydrothermal vein system of the Barberton greenstone belt in South Africa." Astronomers report the detection, for the first time, of an isotope in the atmosphere of an exoplanet. In specific, the isotope Carbon-13 (13C) was found in the atmosphere of a gas giant exoplanet named TYC 8998-760-1 b. Researchers used a brain-computer interface to enable a man who was paralyzed since 2003 to produce comprehensible words and sentences by decoding signals from electrodes in the speech areas of his brain. Researchers describe effects of deforestation and climate change in a transformation of Amazonia from carbon sink to carbon source (see above). 15 July – Scientists report that the Chicxulub impactor likely was an outer main-belt asteroid, a carbonaceous chondrite C-type asteroid. 16 July Recently thought subglacial lakes under the Southern Polar cap of Mars based on a 2018 MARSIS measurement could also be clay minerals and frozen brine. Japan achieves a new world record Internet speed over ~3.000 km: 319 Tbit/s, beating a previous record of 178 Tbit/s. A study concludes only 1.5-7 % of "regions" of the modern human genome to be specific to modern humans.

These regions have neither been altered by archaic hominin DNA due to admixture nor are shared with Neanderthals or Denisovans according to their used genomic datasets. They also found two bursts of changes specific to modern human genomes which involve genes related to brain development and function. A study using whole-genome resequencing indicates that Cannabis sativa was first domesticated about 12,000 years ago in the early Neolithic period in East Asia, with the results being consistent with a single domestication origin. 18 July – Journalists and researchers report the discovery of spyware, called "Pegasus", developed and distributed by a private company which can and has widely been used to infect iOS and Android smartphones often – partly based on 0-day exploits – without the need for any user-interaction or significant clues to the user and then be used to exfiltrate data, track user locations, capture film through its camera, and activate the microphone at any time.

19 July Researchers review 217 analyses of on-the-market products and services as well as existing alternatives to mainstream food, holidays, and furnishings, and conclude that total greenhouse gas emissions by Swedes could be lowered by to date up to 36–38 % if consumers – without a decrease in total estimated expenditure or considerations of self-interest rationale – instead were to obtain those they could assess to be more sustainable. Researchers report that higher exposure to woodland urban green spaces is associated with improved cognitive development and risks of mental problems for urban 15-16 years old adolescents. Scientists report that wild pigs are causing soil disturbance that, among other problems, globally results in annual carbon dioxide emissions equivalent to that of ~1.1 million passenger vehicles, implying that wild pig meat – unlike other meat products – has beneficial effects on the environment.

Figure 3: List of Blockchain Attack Vectors and Vulnerabilities You Should Know ... 20 July Researchers conclude that a previously rejected abiotic origin of phosphine concentrations on Venus reported in September 2020 – high rates of active plume volcanism – could be plausible. A scientific review concludes that, except for poultry, at 50 g/day unprocessed red (~9 % increase) and processed meat (~18 %) appear to be risk factors for ischemic heart disease. Scientists report that worldwide adolescent loneliness and depression increased substantially after 2012 and that loneliness in contemporary schools appears to be associated with smartphone access and Internet use.

4. Practical Deployment, Analysis & Case Studies 22 July Astronomers using the Atacama Large Millimetre/submillimeter Array (ALMA) report the first clear detection of a moon-forming disc around an exoplanet; in this case, the Jupiter-like planet PDS 70c. DeepMind announces that its AlphaFold AI has predicted the structures of over 350,000 proteins, including 98.5% of the ~20,000 proteins in the human body. The 3D data along with their degrees of confidence for accuracy is made freely available with a new database, doubling the previous number of protein structures in the public domain. 26 July The Galileo Project, headed by Avi Loeb, is launched. The project seeks to gather and report scientific evidence of extraterrestrials or extraterrestrial technology – such as of UFOs/UAP with alien origins – on or near Earth via telescope technology. Scientists report to have created the first complete neuron-level-resolution 3D map of a monkey brain which they scanned within 100 hours. A study finds that the increasing probability of record week-long heat extremes occurrence depends on warming rate, rather than global warming level and provides projections. A scientific review summarizes studies about long COVID. 28 July The first direct observation of light from behind a black hole is reported, further confirming Einstein's theory of general relativity. Metallic water is prepared for the first time in an ordinary Earth lab. In an update to the World Scientists' Warning to Humanity, scientists report that evidence of nearing or crossed tipping points of critical elements of the Earth system is accumulating, that 18 of 31 planetary vital signs have reached record values, that 1990 jurisdictions have formally recognized a state of climate emergency, that frequent and accessible updates on the emergency are needed, that COVID-19 "green recovery" has been insufficient and that root-cause system changes above politics are required. 29 July – A study indicates gut microbiomes with large amounts of microbes capable of generating unique secondary bile acids are a key element of centenarians' longevity. 31 July – A kitchen robot – one of the first of its kind – for autonomous preparation of school meal program or delivery-service level amounts of discrete meals is demonstrated.

2 August – Engineers report the development of a prototype wave energy converter that is twice as efficient as similar existing experimental technologies, which could be a major step towards practical viability of tapping into the sustainable energy source. 4 August Scientists identify genetic determinants of ovarian ageing and possible effects of extending fertility in women. Scientists describe the molecular mechanisms by which insect olfactory systems are sensitive enough to recognize and discriminate a vast number of molecules with very few smell receptors. 5 August New observations of the M-type star L 98-59 and its surrounding system reveal three new bodies: a planet in the habitable zone, an ocean world, and a planet with half the mass of Venus, making it the lightest exoplanet ever to be measured using the radial velocity method. A study introduces an early-warning indicator for critical transitions of the Atlantic Meridional Overturning Circulation (AMOC) and finds early-warning signals in eight independent AMOC indices. A, possibly abrupt, likely irreversible collapse from the current strong to a weak mode is thought to have severe impacts on Earth system components and global climate. The Sixth IPCC report assesses a 'medium confidence' that such a collapse won't happen by 2100. 8 August – The National Ignition Facility achieves a 70% yield, compared to the laser energy required to sustain fusion, from inertial confinement fusion energy, an 8X improvement over previous experiments in spring 2021 and a 25X increase over the yields achieved in 2018. 9 August The Intergovernmental Panel on Climate Change (IPCC) releases the first part of its Sixth Assessment Report, which summarizes the state of physical science on climate change based on over 14,000 papers and concludes that effects of human-caused climate change are now "widespread, rapid, and intensifying". Neuroscientists show that transplantation of fecal microbiota from young donor mice into aged recipient mice substantially rejuvenates the brains of the latter, complementing similar results of a 2020 study. A scientific review assesses the long-term effects of COVID-19, including in prevalent cases of long COVID. A researcher reports that solar superstorms would cause global months-long Internet outages. She describes potential mitigation measures and exceptions – such as user-powered mesh networks, related peer-to-peer applications and new protocols – and the robustness of the current Internet infrastructure. 10 August A study based on OSIRIS-REx data concludes there to be a 1:1750 chance of an impact of asteroid (101955) Bennu by 2300, with the highest chance of impact being in 2182. A small-scale study suggests that persistent blood clotting is a cause of long COVID. 11 August – Researchers report promising results of ongoing testing and development of an engineered monoclonal antibodies based female contraception. 12 August – Scientists report that the Ayta Magbukun people in the Philippines have the highest level of Denisovan ancestry in the world and describe the related genetic history in the region. 13 August – Researchers demonstrate that probiotics can help coral reefs mitigate heat stress, indicating that such could make them more resilient to climate change and mitigate coral bleaching. 16 August Scientists conclude that personal carbon allowances could be a component of climate change mitigation. They find that the economic recovery from COVID-19 and novel digital technology capacities open a window of opportunity for first implementations of such monetary/credit feedback and decreasing default levels of emissions concessions. Researchers assess regionally-differentiated drivers and risks associated with worldwide pollinator decline, informing globally-relevant policy responses. 17 August – Scientists report of human brain organoids that could intrinsically develop eye-type sensory structures. 18 August – A study suggests that the global policy Montreal Protocol intended to control the production of ozone-depleting substances has also substantially mitigated climate change. 20 August – Medical scientists confirm that hormone irisin confers neurobiological effects of physical exercise and, when its circulating levels are increased, can be an exercise mimetic in mice which may be useful for interventions to improve cognitive function or alleviate Alzheimer's disease. 22 August – Astronomers conclude in a preprint that – controversially due to there being only few data points – there is high confidence "Planet 9" exists, that it likely has a mass of ~6.2 Earths and is closer than thought previously and report its likely orbit.

24 August Cerebras announces a new hardware and software platform that can support AI models of 120 trillion parameters, enabling neural networks greater than the equivalent number of human brain synapses. Researchers present a bioprinting method to produce steak-like cultured meat, composed of three types of bovine cell fibers. 26 August – Astronomers report a new class of habitable exoplanets, named hycean planets (from hydrogen and ocean), which are described as hot, water-covered planets with a hydrogen-rich atmosphere that are possibly capable of harboring life. 27 August – Scientists report about vaccine effectiveness, pandemic severity impacts and regional prevalence of SARS-CoV-2 Delta variant overall and its newly subdivided subvariants named from AY.1 onwards, the first two of which were differentiated like so – also termed "Delta Plus" – in June. On 10 August a preprint reports a case of asymptomatic transmissions associated with high viral load among vaccinated patients infected by AY.3. 28 August – The world's northernmost island, a small patch of land measuring 60 x 30 metres, is reported by scientists off the coast of Greenland. The name Qeqertaq Avannarleq is proposed, which means "the northernmost island" in Greenlandic. 30 August The comprehensive 2021 ESC Guidelines on cardiovascular disease prevention is published. On 27 August the 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure is published. A preprint study of nationwide data of Israel's vaccination programme finds a strong effect of waning immunity from the Pfizer-BioNTech COVID-19 vaccine after 6 months. 31 August – Scientists report that the Paleocene–Eocene Thermal Maximum ~56 million years ago was directly preceded by volcanism and that data about the event supports the existence of substantial climate-shifting tipping points in the Earth system.

2 September Observation of a new class of supernova triggered by a black hole or neutron star crashing into the core of a companion star is reported by astronomers, based on studies of an extremely luminous source of radio waves called VT 1210+4956. Astronomers report the detection of peculiar radio waves from near the galactic center whose unidentified source could represent a new class of astronomical objects. A study finds that outdoor air pollution is associated with substantially increased mortality "even at low pollution levels below the current European and North American standards and WHO guideline values". On 22 September, for the first time since 2005, the World Health Organization (WHO), after a systematic review of the accumulated evidence, adjusted their air quality guidelines whose adherence could save millions of lives, protect against future diseases and help meet climate goals. 3 September Bioengineers report the development of a viable CRISPR-Cas gene-editing system, "CasMINI", that is about twice as compact as the commonly used Cas9 and Cas12a.

Researchers report that autoantibodies against one's own ACE2 enzymes (the major entry point receptors for COVID-19), autoimmune disease, may be a (main) cause of long COVID. Earlier studies suggested this may explain unusual pattern of organ damage by COVID-19. Scientists report that the accelerated, higher-variability warming of the Arctic can cause (more frequent) extremely cold winter weather across parts of Asia and North America – including the February 2021 North American cold wave – via a, observed and modeled, stratospheric polar vortex disruption. 6 September – Experts report that one-third of all chondrichthyes fish species are threatened with extinction, mainly caused by overfishing. 8 September Cysteamine, an antioxidant drug already approved for human use, is shown to reverse atherosclerosis, the process responsible for heart attacks and strokes, in mice. Scientists provide the first scientific assessment of the minimum amount of fossil fuels that would need to be secured from extraction per region as well as globally, to allow for a 50% probability of limiting global warming by 2050 to 1.5 °C. Scientists report that Earth is reflecting less light – a dimming of ~0.5% in reflectance over two decades may have both been co-caused by climate change as well as substantially increase global warming. 10 September Scientists report what could be the discovery of the oldest rock art, likely dating back to ~169–226,000 years ago, much older than what was previously thought to be the earliest known drawing, made ~73,000 years ago. Children likely intentionally placed a series of hands and feet in mud. The findings could also be the earliest evidence of Hominins on the above 4000 m a.s.l. high Tibetan Plateau. 43 expert scientists publish the first scientific framework version that – via integration, review, clarifications and standardization – enables the evaluation of levels of protection of marine protected areas and can serve as a guide for improving, planning and monitoring marine protection-quality and -extents such as in efforts towards the 30%-protection-goal of the "Global Deal For Nature" and the UN's SDG 14. The CDC reports that despite prevalence of the Delta variant people vaccinated against COVID-19 are ~11 times less likely to die from COVID-19 (age-standardized rates of 1.6 versus 0.1 and 1.1 versus 0.1 weekly deaths per 100,000 U.S. citizens), showing vaccines' effectiveness at preventing severe disease.

13 September – A scientific review concludes that accumulating data suggests dietary restriction (DR) – mainly intermittent fasting and caloric restriction – results in many of the same beneficial changes in adult humans as in studied organisms, potentially increasing health- and lifespan. A review published on 22 September provides an overview of DR as an intervention and develops a framework for a proposed field of "precision nutrigeroscience". A study published on 29 September identifies circadian-regulated autophagy as a critical contributor to intermittent time-restricted fasting-mediated lifespan extension in Drosophila and suggests that only certain forms of and/or combinations with intermittent fasting – intervals during which no food but only e.g. water and tea/coffee are ingested – may be effective beyond the benefits of healthy body weight. 15 September Physicists report candidate dark energy particles, Sun-produced local environment-adjusted "chameleon particles", at the dark matter detector XENON1T experiment. Scientists confirm that widespread phytoplankton blooms can be a feedback effect of wildfires. The climate change-exacerbated 2019–2020 Australian wildfires caused oceanic deposition of wildfire aerosols, enhancing marine productivity and thereby increased oceanic carbon dioxide uptake. A study using satellite data complements these findings, constraining the amount of CO2 emissions of the fires from November 2019 to January 2020 to around 715 million tons. Media outlets report that the world's first cultured coffee products have been created by two biotechnology companies, still awaiting regulatory approval for near-term commercialization. Such products, for which multiple companies' R&D have acquired substantial funding, may have equal or highly similar effects, composition and taste as natural products but use less water, generate less carbon emissions, require less labor and cause no deforestation. 16 September – Scientists report evidence of clothes being made 120,000 years ago based on findings in deposits in Morocco, a country in the northwestern part of Africa. 17 September Scientists report that harmful algal blooms, which have been linked to deforestation, global warming and soil erosion, are proliferating in lakes and rivers around the globe. They add that such toxic algal blooms were a prominent feature of previous mass extinction events, in particular of the End-Permian Extinction. Researchers report in a preprint the discovery of i.a. the so far closest known relative virus, with a 96.8% similarity, to SARS-CoV-2 in samples from wild horseshoe bats in northern Laos – 0.7% more similar than the virus RaTG13 discovered in China in 2013. Their findings indicate that, as of 2021, SARS-CoV-2-like viruses potentially infectious for humans circulate in bats in the Indochinese peninsula and that the pandemic virus may not originate from Wuhan. Other scientists complement these findings, reporting in a preprint published on 20 September, that they could not find any SARS-CoV-2 related viruses in any samples collected in China, including from the only two domestic caves where RaTG13 and RmYN02 were detected, indicating such viruses may currently not circulate in bats in the country.

22 September – Astronomers report the discovery of a nearby spherical structure, a 'superbubble', on the edges of which giant molecular clouds (Perseus and Taurus) with regions of star formation are being formed, the Per-Tau Shell. 23 September Scientists report the discovery of human footprints in the state of New Mexico that are understood to be ~23,000 years old, around the time of the last Ice Age. Researchers report the world's first artificial synthesis of starch. The material essential for many products and the most common carbohydrate in human diets was made from CO2 in a cell-free process and could reduce land, pesticide and water use as well as greenhouse gas emissions while increasing food security. After commissioning two impact assessment studies and a technology analysis study, the European Commission proposes the implementation of a standardization – for versions of USB-C – of phone charger products, which may increase device-interoperability, convergence and convenience for consumers while decreasing resource-needs, redundancy and electronic waste.

5. Performance Evaluation & Extended Technical Observations 24 September Researchers conclude that projecting effects – such as regional inhabitability, human migration and food insecurity – of greenhouse gas emissions only for up to 2100, as widely practiced in research and policy-making, is short-sighted and model climate change scenarios for up to 2500. Media outlets report that in Japan the first CRISPR-edited food has gone on public sale. Tomatoes were genetically modified for around five times the normal amount of possibly calming GABA. CRISPR was first applied in tomatoes in 2014. Biomedical researchers demonstrate a switchable Yamanaka factors-reprogramming-based approach for regeneration of damaged heart without tumor-formation in mice. 26 September – Researchers estimate that children born in 2020 (e.g. "Generation Alpha") will experience 2–7 times as many extreme weather events, particularly heat waves, compared to people born in 1960 (e.g. "Baby Boomers" and "Generation X") under current climate policy pledges over their lifetimes, raising issues of intergenerational equity. 27 September Landsat 9, described as the world's most important satellite, is launched by NASA to study the Earth and its environment. Biochemists and space scientists report that sunlight-, acidity- and water activity-levels in Venus' clouds may have the potential to support Earth-like phototrophy such as photosynthesis. 28 September Medical scientists report that COVID-19 measures may have, apparently, caused the global extinction of the influenza B virus lineage B/Yamagata. Pathogen researchers report the development of machine learning models for genome-based early detection and prioritization of high-risk potential zoonotic viruses in animals prior to spillover to humans. They conclude that their tool could be used for virus surveillance for pandemic prevention via (i.a.) measures of "early investigation and outbreak preparedness" and would have been capable of predicting SARS-CoV-2 as a high-risk strain.

11 October Scientists report more precise dating of what appear to be the earliest bipedal footprints with hominin-like characteristics, the Trachilos footprints. They are found to be ~6.05 million years old, which is around the time of Orrorin – the previously earliest theorized species of Homininae until these footprints were controversially dated in 2017, despite being discovered outside of Africa in Crete, Greece. However, these apes are not necessarily associated with human evolution. The pilot project of the "world's first automated, driverless train" is launched in the city of Hamburg, Germany. The conventional, standard-track, non-metro train technology could theoretically be implemented for rail transport worldwide and is reported to also be substantially more energy efficient. Scientists project public health impacts, along with some of the environmental damage, of a, simulated, imminent Red Sea oil spill from the FSO Safer. 12 October – Scientists report that for 13,115 cities extreme heat exposure of a wet bulb globe temperature above 30 °C tripled between 1983 and 2016. It increased by ~50% when the population growth in these cities is not taken into account. Urban areas are often significantly warmer than surrounding rural areas. 13 October – Astronomers report the detection of hundreds of Fast Radio Bursts (FRBs) from a single system. 15 October – The first brain metabolome atlas of the mouse brain – and of an animal (a mammal) across different life stages – is released. 16 October The spacecraft Lucy is launched by NASA, the first mission to explore the Trojan asteroids. A comprehensive study by Scientists for Future concludes that nuclear fission energy cannot meaningfully contribute to climate change mitigation as it is "too dangerous, too expensive, and too sluggishly deployable" as well as "an obstacle to achieving the social-ecological transformation". 18 October – A study shows for the first time how immunity is inherited, via epigenetic changes, in mice (mammals). 19 October – Media outlets report about novel technologies for virtual try-ons of clothes for more sustainable fashion and improved online shopping, which increased relatively due to the COVID-19 pandemic.

20 October Astronomers report the first evidence of a giant impact between two exoplanets, which occurred in the HD 172555 system, based on analysis of gas and dust concentrations. Scientists report that, according to their analysis, today's domestic horses descend from the lower Volga-Don region, Russia. 273 ancient horse genomes further indicate that these populations replaced almost all local populations as they expanded rapidly throughout Eurasia from about 4200 years ago, that certain adaptations were strongly selected for by horse riding, and that equestrian material culture – including Sintashta spoke-wheeled chariots and in the case of Asia Indo-Iranian languages – spread alongside. Researchers report on the first natural protein that, using lanmodulin, complexes actinium, a natural but radioactive element used in cancer therapy, alongside yttrium-90. 21 October Medical researchers announce that on 25 September the first successful xenotransplantation of a genetically engineered pig kidney, along with the pig thymus gland to make the immune system recognize it as part of the body, to a brain-dead human with no immediate signs of rejection, moving the practice closer to clinical trials with living humans. A study shows how COVID-19 may inflict long-term brain damage, including in cases of 'long COVID', via endothelial cell-death disrupting the blood–brain barrier. 22 October Researchers describe and substantiate the hypothesis that a recent decrease in brain size "in the last 3,000 years" (previously thought to instead have occurred during the last ~28,000 years) has resulted from externalization of knowledge and group decision-making, partly via social systems of distributed cognition and sharing of information. A study by Villmoare et al. (2022) that reanalyzes the used data refutes their findings. It concludes that "the samples need to be specific enough to test the hypothesis across different times and populations". A study shows that mandatory face masks and social distancing can allow for relatively safe public transport during the COVID-19 pandemic, reducing infection rates by 93.5% and 98.1% in tracking-based simulations of common contemporary forms of public transport during congestion peak-hour. 25 October Astronomers report, with two studies, that 'BLC1' does not appear to be a technosignature or extraterrestrial radio transmission because 15 similar observations were made between 2019 and 2020 that did not originate from around Proxima Centauri – and hence are likely results of forms of local radiofrequency interference – and propose a sequence of "verification checks for narrowband technosignature signals".

Another, clearer case of quantum advantage with Zuchongzhi is reported. A third study reported that Zuchongzhi 2.1 completed a task of classically simulating random circuit sampling that "is about 6 orders of magnitude more difficult than that of Sycamore". 27 October Astronomers propose a "Confidence of Life Detection" scale (CoLD) for reporting evidence of life beyond Earth.

Astronomers report that the orbits of the detected exoplanets hosted by the star HD 3167 are unusual: two planets (HD 3167 c; HD 3167 d) revolve around the poles of the star, whereas the third planet (HD 3167 b) orbits around the equator of the star instead. Researchers release a "policy sequencing" framework, in particular for policies of polycentric governance for completely halting and preventing deforestation based on data about already implemented government-designed policies, UN-decided REDD+ initiatives and voluntary private sector initiatives of recent deforestation interventions. The world's first urban autonomous vessels, 'Roboats', are deployed in the canals of Amsterdam, Netherlands. The ships developed by three institutions could carry up to five people, collect waste, deliver goods, and provide "on-demand infrastructure". A potentials-assessment study proposes hypothetical portable solar-powered atmospheric water harvesting devices which are under development, along with design criteria, finding they could help a billion people to access safe drinking water, albeit such off-the-grid generation may sometimes "undermine efforts to develop permanent piped infrastructure". 28 October An open letter by almost 300 scientists asks the WTO to eliminate increasing harmful fisheries subsidies. One year after India and South Africa called on WTO to temporarily waive TRIPS vaccine patents for accelerated deployment of COVID-19 vaccines around the world, the WTO reportedly fails to find an accord for doing so. No mechanisms of alternative medical research and development incentive-systems or technical details of proposed "sharing" after certain amounts of profit were reported and some argue that, instead of intellectual property rights, manufacturing know-how is the main barrier to expanding capacity. Scientists discover that up to about 20,000 metric tons of microplastics may be stored in coral skeletons worldwide every year, marking the first time that a living microplastic "sink", or long-term storage site, has been quantified. 30 October – A comprehensive review summarizes scientific research and data about health impacts of climate change.

2 November – A study concludes that PM2.5 air pollution induced by contemporary forms of free trade and consumption by the 19 G20 nations (the EU as a whole is not included) causes two million premature deaths annually, suggesting that the average lifetime consumption of about ~28 people in these countries causes at least one premature death (average age ~67) while developing countries "cannot be expected" to implement or be able to implement countermeasures without external support or internationally coordinated efforts.

Harvested Online Documentation & Reference Sources • https://en.wikipedia.org/wiki/Video%20game%20modding • https://en.wikipedia.org/wiki/2021%20in%20science