輻射世界是一個管家機器人投入應用，小型激光武器成為常態的世界。汽車看起來都像是20世紀50年代的概念車：鍍鉻，有着巨大的尾翼，並且由核聚變發動機提供動力。雖然有類似於台式電腦的終端機(外觀與20世紀80年代商業化的台式電腦相似，圖形界面原始且儲存容量極小)，但計算機的體型普遍巨大，並使用磁帶儲存(雖然樣式古老，但在某些方面比我們現代的超級計算機更加強大)。服裝風格，建築，裝修和傢具仍舊嚴重受到20世紀50年代美國文化的影響，這一時期的流行風格，如藝術裝飾風格和未來主義仍然在輻射世界中有普遍體現，海報和標識也傾向20世紀50年代的風格。電台，而不是電視，仍然是最普遍的大眾媒體，並且食品也是快餐時代中所普及的(如盒裝芝士通心粉，肉罐頭，索爾茲伯里牛肉餅等)。廣播電台主要播放20世紀中葉的美國經典，如The Ink Spots，貓王和Andrew Sisters，儘管這可以解釋為只有這些唱片在大戰後倖存。
在輻射世界中，20世紀50年代偏執的政治觀點和共產主義與資本主義兩大陣營的對立，仍是北美地區人們日常生活的一部分。例如在Take it Back!任務中，自由金剛高喊的口號“Death is a preferable alternative to communism!”(比起共產主義，死亡是更好的選擇！)對應50年代“Better dead than Red!”的反共口號。反共宣傳在美國流行文化中似乎也有體現，如電子遊戲(Red Menace，即紅色威脅 等)和漫畫(Commie-Kazi vs. Manta Man,即蝠鱝俠vs共產海豚)等。
輻射世界與現實之間的差異最早形成的時間尚不清楚，但應該不會早於1945年——也就是第二次世界大戰結束的那一年。產生差異的一個可能的原因是輻射世界裡的電子設備發展水平不及現實世界——比較有力的證據是在輻射世界中，晶體管直到2023年才被發明出來，遠遠晚於現實世界中的1947年。這或許能夠解釋為什麼遊戲中的電腦技術為什麼相對落後。事件對應的日期很難確定，因為即使在時間線分歧之後，兩個時間線也並不是完全錯開的。 例如，Fallout 3 中核彈鎮的某些居民偶爾會說“不要讓他們打着嬉皮士的幌子欺騙你”，以及 Fallout: New Vegas 隱秘山谷地堡的塗鴉包含反核，親 “和平”口號，讓人聯想到60年代反主流文化所使用的口號。 雖然“嬉皮”一詞早在1945年就已存在，但它直到20世紀60年代才進入主流美國詞典中。很明顯，類似於我們世界中嬉皮反文化的興起也發生在輻射宇宙中，或者嬉皮士運動也可能正常發生。 Fallout 4 的開頭動畫也表明，對廣島和長崎的轟炸等第二次世界大戰的事件以同樣時間與方式發生，證明了1945年是時間線分歧前的最後時間點。
雖然輻射的時間線與我們的時間線在1945年之後的某個時間發生了重大分歧，但是在1945年之前的輻射時間線中也發生了一些與我們的時間線不同的事件。 然而，這些都不會對人類歷史產生重大影響。 這些差異中最值得注意的是在地球軌道上存在一個外星宇宙飛船，以及至少1603年以來對人類進行的外星人相關的綁架和實驗。其他輻射時間線獨有事件的例子包括： 1918年首次製造夕陽沙士，1932年維姬和萬斯的犯罪狂潮，以及Vim! 流行公司 於1931年的成立，在第二次世界大戰結束的十多年前。 1943年建造的密蘇里號在自由博物館的壁畫中的不同之處在於，她有4個主炮塔，而不是3個。
在時間線分歧之後美國國旗的更改，證明美國發生了巨大的變化。 在1969年，50個州被鞏固（加利福尼亞則是分裂）為13個聯邦，儘管看起來各州本身保留了一定程度的主權（從米歇爾醫生房屋外面的內華達州旗以及各種車牌裝飾上有州名而不是聯邦名稱可以看出 ），However, this could be seen as a way to make organizing plates a lot easier, as merging three states into commonwealths would lead to 3 duplicate plates.
時間線分歧的其中一點是戰前美國的價格膨脹。 可能是因為化石燃料的稀缺，戰時支出以及世界性的政權不穩定，美元在大戰前的幾年中經歷了嚴重的通貨膨脹。 許多東西，從汽車，汽油到玩具和食品，價格都遠高於我們的世界。 值得注意的例子是：
- 像波士頓號角報和華盛頓郵報這樣的報紙每期售價56美元。漫畫和雜誌，如Guns and Bullets(槍支和子彈,Fallout 4及Fallout: New Vegas版本在此)，Unstoppables(無人能擋)和Astoundingly Awesome Tales(驚世奇譚)，根據具體內容，價格從15美元到33美元不等。
- Chryslus Corvega於2077年上市，價格"僅"為199,999美元。
City design in the Fallout universe differs from that in ours, often to the point that the cities are only superficially similar in layout and presence of familiar landmarks.
Looks similar to the American capital city of our world in terms of the placement of signature buildings and overall urban design, but has some noticeable changes:
- Much of the pre-War contemporary architecture is 1940s/'50s art deco & 1950s/'60s modernist.
- The skyscrapers that define Arlington, Virginia in our reality do not exist.
- Buildings such as the Smithsonian National Air and Space Museum are replaced with the Museum of Technology. Several Smithsonian museums also do not appear in-game.
- Busts of persons apparently famous in the Fallout world while unknown in ours are located on many buildings.
- The Capitol Building has two single flight sets of stairs on its front facade (the side facing the Mall), rather than dual sets of stairs.
- The Mall is smaller and more compressed than the real Mall (though this may just be an instance of the entire Capital Wasteland being smaller and more compressed than the real D.C. area)
- The subway network is different; there are fewer lines and the stops are different (the D.C. subway network in Fallout 3 has 3 lines, Red, White and Blue), while the real D.C. subway has 6 lines (Red, Orange, Yellow, Blue, Green, and Silver), though admittedly the Silver Line was still a plan-in-development at the time of Fallout 3's release and had not even received funding to begin its construction.
- The Washington Monument has a steel skeleton, which the real monument doesn't have.
- The Pentagon is located in a different location than our universe, being right on the banks of the Potomac next to the Arlington Memorial Bridge.
- An elevated monorail network ran through the city and surrounding areas. No monorail networks exist in D.C. in our timeline, though some parts of the "subway/metro" are in fact elevated above ground, for example the Red Line between Union Station and Forest Glen, or the Yellow line where it crosses the Potomac River.
- Many buildings and memorials built since the 1950s and 1960s in our timeline (such as the Vietnam War Memorial, the World War II Memorial, Nationals' Park, Korean War memorial, FDR memorial, Theodore Roosevelt memorial, the Kennedy Center, the Newseum, Etc) either were never built or were destroyed and totally forgotten.
- Union Station does not appear in-game.
- The Supreme Court does not appear in-game.
- Factories remain fairly common, as was the case during the American industrial economy of the 1940s-1960s, and, while heavily automated with robotics, are still quite primitive by our present-day standards.
- Towering highways criss-crossed the area, in some areas standing 85-100 feet off the ground, even running through Central Boston.
- Quincy Market, which opened in 1825 opposite Faneuil Hall does not exist, and neither does the ring of stores surrounding it.
- Sanctuary Hills does not have a Minuteman Statue on the right side of the road exiting the neighborhood, but rather a completely different statue of a Minuteman in the middle of the road. The bridge used for entering and exiting Sanctuary Hills is in fact, a reality, as it does exist. The last thing is, there is no neighborhood in Sanctuary Hills, but rather an open area of land.
- The Strip, as well as the greater remains of Las Vegas proper in the Fallout universe appear to be a lot smaller than the city in our world. A large number of Las Vegas' casinos and prominent structures also seem never to have been built, instead replaced by similar buildings or simply nonexistent.
- Nellis Air Force Base as it exists in the Fallout universe appears isolated and relatively distant from Las Vegas. However, while the location is mostly geographically accurate, the real base is surrounded by urban sprawl and far less removed from it.
- Hoover Dam is significantly shorter than its real counterpart, and also lies much closer to Las Vegas than the dam does in the real world. The exterior of the dam is mostly accurate to the real thing in appearance, but the interior diverges significantly.
- Mike O'Callaghan–Pat Tillman Memorial Bridge, which runs adjacent to Hoover Dam and carries traffic from Route 93 (which previously ran across the dam itself), does not appear to have been built. However, the bridge was only completed on October 14, 2010, mere days before Fallout: New Vegas was released.
- The B-29 Superfortress submerged at the bottom of Lake Mead, while real, is in significantly worse shape in the real world and far more corroded than it appears in Fallout: New Vegas even in the present day (let alone 200+ years in the future when 2281 comes to pass.)
- The Lighthouse that appears in-game looks very different in real life.
- The city still is and has grown for steel industries to the point where there are factories and steel yards in the uppertown area, in the Fallout universe. But for our timeline, in Pittsburgh, the steel industry has mostly gone out of business.
- The Pitt Bridge before the war was actually a updated version of the Wabash bridge in the Fallout universe. As for our timeline the Wabash bridge was demolished in 1948 after years of neglect. Two piers remain in places today, the only remnants of the bridge still in place at the original site in our timeline.
- The Coast around Far Harbor (Bar Harbor in our world) appears to be a lot higher than in our world.
- The Cathedral is a prominent building that was built post-war and appears in the original Fallout is not in the real world.
- The character on the Camden Park sign is different than the one used in real life (which is a clown). The park is also missing a few rides/attractions as well as certain areas of the park such as the picnic shelter.
- Huntington and Wheeling don’t appear in game, whereas they are two of the largest cities in WV in real life.
- Flatwoods is much smaller featuring only a small version of the older town and much if not all of the newer areas don’t appear.
- West Virginia University is now known as Vault-Tec University.
- The Greenbrier Resort has been renamed to the Whitesprings Resort.
- Hillbilly Hotdogs has been renamed to Hillfolk Hotdogs.
- The New River Gorge Bridge appears right over Flatwoods in game where as in real life they are further away from each other.
- The Mothman statue in Point Pleasant doesn’t have arms where as it does in real life.
- Greenbank is on a hill where as in real life it’s in a large field; it has also been renamed in-game.
- The Summersville lighthouse is further away from the lake than it is in real life and is renamed in-game.
- The Tamarack does not appear in-game.
- The Pumpkin house is far to the north east in game, where as in real life it is to the south west near Kenova and Huntington.
與現實相比，輻射世界最大的區別之一在於數字計算機和電子產品沒有出現小型化趨勢。最突出的例子是晶體管，在現實世界中早在1947年便被發明出來，並在隨後的半個世紀中掀起一場微電子革命。但在輻射世界中，晶體管直到2067年才發明，而它的後繼產品——半導體微處理器芯片更是從未出現過。這直接影響了輻射世界中的數字計算機發展，在遊戲中，計算機並不像現實里的那樣普及，而且它們大多採用老式的磁帶作為存儲介質，不僅內存狹小，還需要佔用大量的安放空間。輻射世界中的個人計算機雖然小很多，但同現實相比，他們依然顯得很笨重，而且基本上都採用單色的陰極射線管顯示器，帶有一體式的鍵盤，外觀上近似於現實中1970年代的Intertec Superbrain計算機，以及蘋果公司設計師哈特穆特·艾斯林格為Apple II計算機設計的原型。不過不可否認的是，這些計算機大都十分堅實、可靠，甚至在被製造出來210年後還可以正常運作。However, they are evidently built to be extremely sturdy, weather resistant and reliable, as functioning examples can be found 210 years after the bombs fell, often in harsh conditions functioning perfectly fine. Data is stored on holotapes or holodisks which electromagnetically store information as three-dimensional digital images. These computers are very advanced in their processing power, indicating that progress continued in computer science (albeit at a slower rate than in our universe), but the technology to make them smaller never emerged on a large scale: technologies like the Pip-Boy and androids require miniaturized electronics to function. Nor did user-friendly icon-based graphical user interface (GUI) operating systems, which first appeared commercially in our world in the 1980s. UIs remained fairly basic command-line affairs, and less frequently advanced voice interfaces (as per computers in 1950s science fiction) were developed for computer systems which made a GUI redundant on such systems.
Television sets and radios also failed to evolve past the early 1960s level, and television in the Fallout universe remained in the same monochromatic hues as its computer screens, as well as having tiny displays and large frames. However, color television seems to not be prominent in the Fallout universe despite the fact that color television first became mainstream in 1953. Another example of technology failing to evolve can also be found in cameras. Cameras in the Fallout universe are big and bulky with large flash bulbs like those used in the late '50s and '60s. Interestingly enough, however, the CCTV cameras seen in Fallout games are just as compact as those in the real world.
Various references to uploading and downloading, as well as to e-mail and networked communications, also demonstrate that though the Fallout universe lacks our mastery of microprocessor technology, other aspects of computer science proceeded unhindered, such as robotics, the development of the Internet, and orbital communications satellites.
In the Fallout world, nuclear power was not only used for atomic bombs, it was also harnessed in nuclear reactors, which became a prominent source of energy. Large scale fission reactors that powered whole towns as in our world existed, but were a lot more common. These power plants were smaller and they often existed underneath towns and cities, such as the one in New York that almost went into meltdown and the powerworks beneath Olney. But similar to our world where more priority was put towards making electronics smaller, more priority was put towards making nuclear reactors smaller in the Fallout universe.
They were reduced in size to the extent that they could be used in roles more typically occupied by internal combustion engines in our world, such as car engines and small electrical generators, or even in fission batteries. Controlled nuclear fusion, a source of energy which is yet to be harnessed by scientists of our world, was developed. Fusion reactors were used to power vehicles and, like fission reactors, were reduced to very small sizes for use in power cells which were the standard for powering medium energy weapons in the military. Many of these pre-War power sources are still functioning around the time of Fallout 3 and Fallout: New Vegas. One example of functioning mini reactors are the ones in radios and televisions across the wasteland. It is seen in the demo video of Fallout 3, that there is a mini reactor still pumping out energy in a destroyed bus radio. This also explains the lack of power cords on the radios and televisions in the wastes.
This nuclear obsession of the Fallout world saw nuclear energy and, to a lesser extent, radioactive materials, being utilized wherever possible; even seeing radioactive isotopes added to a type of cola at one point despite the inevitable health risks of ionizing radiation. Their world's obsession with nuclear energy ultimately ended in the destruction of pre-War society.
Along with this proliferation of nuclear technologies came the risk of radiation poisoning during accidental radiation exposure. In response to this threat, radiation treatment and inoculation technologies were developed in the Fallout universe. Such technologies have yet to be realized in our timeline beyond very early experiments.
All of the Fallout games use a combination of fictional weapons and weapons similar or identical to real-world examples. The games vary in their faithfulness to canon and logic in their choices of which weapons are included as well as in how the weapons' characteristics have been modified from their real-world counterparts.
The development of nuclear weapons in the Fallout world differed from our universe in that the majority of nuclear weapons remained in aircraft-delivered bomb form, while only a minority were miniaturized into warheads and placed atop ballistic missiles. The progress of nuclear weapons apparently stayed at the atom bomb level and improving upon it; thermonuclear and hydrogen bombs were either never researched or abandoned in favor of atom bombs. There are a few examples of a nuclear missile in-game: the Minuteman ICBM in Fort Constantine. Other areas, such as Fort Bannister and the Wheaton Armory, have missile silo doors that are similar to the one found at Fort Constantine but feature no apparent way to launch missiles. This suggests that the missiles in these facilities were launched during the Great War. In The Divide, there are a large number of un-launched ICBM's, suggesting they were prepped for launch, but never got the call during the short period of mass destruction. It is suggested that nuclear-capable countries, such as the U.S. and China, had begun converting their nuclear stockpiles to ballistic missile form by the time of the Great War in 2077. Aircraft-delivered nuclear weapons took the form of the old-style bombs used in the 1940s and 1950s, similar to the Fat Man dropped on Nagasaki in World War II. Although electronic miniaturization was accomplished in the Fallout universe, nuclear bombs of the late twenty-first century still retained the Fat Man-esque shape. However, in New Vegas, Mr. House mentions having defended the city from 77 nuclear missiles, suggesting that the Chinese at least had access to substantial numbers of warheads in missile form. Also, information on the computer terminals found in the Washington, D.C. Museum of Technology would suggest that the American military recommissioned the Delta IX rockets as nuclear warhead vectors. Additionally, the "Minuteman" series of nuclear missiles (First launched in 1962 in our universe) appear to have also been developed and expanded on in the Fallout world, as "Minuteman XI" missiles appear in both Fallout 3 and Fallout: New Vegas, while the Minuteman III is the latest in our world.
Rifles retained designs of weapons that originated in the 1940s and 1950s, such as the AK47 or FN FAL. There is evidence that despite the diverging timelines, weapons development in the Fallout universe followed a similar path to ours. Picatinny rails (a technology that is only recently been implemented in our universe) as well as weapons such as pump-action grenade launchers and break-action grenade rifles, which were developed around the 1960s for the Vietnam War in our timeline. Handguns also retained similar designs to those of the early 20th century. Heavy weapons, such as missile launchers and the Fat Man, had unique designs such as side mounted foregrips and pneumatic ammunition loading systems. Weapons that seem impractical in our timeline, such as nuclear catapults and man-portable miniguns, were extensively developed in the Fallout timeline and issued to frontline troops. Ammunition calibers that are not common in our timeline, such as the 10mm, are widely used in the Fallout era, while common ammunition in our timeline, such as .50 BMG, .45 ACP, etc. is utilized for more specialized roles, such as high caliber rifles and submachine guns.
Guided missiles exist in the Fallout timeline, but are much less commonly used. As mentioned above, intercontinental ballistic missiles existed during the Great War, however, most nuclear weapons appeared to be free-fall bombs. Smaller hand-held Missile launchers capable of locking onto targets, particularly metallic targets such as robots or turrets with the Vault-Tec Assisted Targeting System also exist, possibly originally intended as anti-tank, anti-power armor, and/or anti-robot weapons. Guided missile cruisers such as the USS Ebon Atoll were also in service with the US Navy by the 2050s. In spite of the development of handheld and naval missile systems, aircraft launched air-to-air or air-to-ground missiles may not been invented until the time of the Great War, as the primary armament of Great War-era Fighter jets of the game appear to be armed only with nose-mounted machine guns, suggesting aerial warfare tactics changed little since the 1950s. Guided missile launchers have only been confirmed on the cutting-edge Vertibird VTOL aircraft.
異塵餘生宇宙有三臺重要的衛星軌道武器。一臺代號為Highwater-Trousers（短管長褲）的軌道飛彈平臺，在異塵餘生3中可透過衛星站的終端機使用。一臺名為Bradley-Hercules（布萊德利-海克力士）的高爆飛彈軌道平臺，此武器在異塵餘生3的拓展包Broken Steel中摧毀了Liberty Prime（自由至尊）。出現於異塵餘生:新維加斯中，搭載雷射的Archimedes II（阿基米德二世）。他們都瞄準了地表上的某個位置，可以消滅任何威脅。遊戲中的對話表明核武器與雷射武器的軌道武器網路都是存在的。
現實世界的衛星軌道武器實例是蘇聯的8K69部分軌道轟擊系統（Fractional Orbital Bombardment System，FOBS），是將裝載核子飛彈的可重返大氣層載具部屬在低地球軌道，可待機無限久並以前所未有的速度於全球發動襲擊，類似遊戲中英克雷的Bradley-Hercules平臺。部分軌道轟擊系統於1982年逐步淘汰，以符合現已失效的SALT II條約，該條約禁止將大規模殺傷性武器部屬到地球的衛星軌道上。
The Fallout universe excelled at robotics technology, to the point that robots permeated pre-War society and served a variety of roles, both military and civilian. Robots walked family pets, retrieved groceries from the store, took care of children, impersonated famous celebrities to the joy of the public and even fought in the military. The types of robots and their physical characteristics varied, ranging from bipedal Protectrons, to tracked and hovering robots like the Robobrain and Mister Handy/Gutsy, to the enormous Liberty Prime robot designed to retake Alaska from the Chinese during the Sino-American War. Robots were often powered by fission batteries and energy cells, meaning many survived the nuclear holocaust of 2077.
Rotary craft such as helicopters do not seem to be prevalent in pre-War society, despite helipads being found on hospitals and high-rises, suggesting they were limited in numbers or only used specialized roles or no wreckage survived the Great War.
Despite the development of jet power, some civilian airliners still use propellers, as evidenced by the aircraft at Camp McCarran in New Vegas. Wrecked jetliners found at Logan International Airport in Boston have enormous frames, being almost the size of a cargo plane and have five nuclear jet engines arranged in a cluster formation on each wing, for a total of 10 engines, with passenger seating integrated into the wing.
Another technological difference between the Fallout universe and our own is the approach taken to plastic polymer use. In the Fallout universe, plastic is far less prevalent than in our own, with glass and metal alloys being the materials of choice. This is likely due to the scarcity of oil in the Fallout universe, which is essential to manufacture plastic. Syringes are glass and reusable, stimpaks come in a glass vial inside a metal casing, etc. Although water seems to come in plastic Polyethylene Terephthalate (PET or PETE) bottles, the shape and size of the bottles themselves suggest they are mainly part of laboratory equipment. Intravenous preparations like RadAway and Blood packs also comes in plastic bags. However, the American military has widely employed plastic polymers - military combat armor is made of advanced defensive polymers, as is the T-51b power armor and later power armor models in the line. In Fallout 4, plastic containers and products are more common, with examples being bottles for automotive products such as coolant and antifreeze, as well as some household products such as bread boxes and dog food bowls. In spite of this, plastics are still far less common in Fallout 4 in real life, as seen with the prevalence of glass stimpak syringes and Nuka-Cola bottles.
Specific teams are never accurately referenced by name because that would require licensing from Major League Baseball, but there are some key divergents in the Fallout timeline to be observed. A terminal in the Boston Bugle building reveals an article that states that "it has been 159 years since this city has reveled in the joy of a World Series victory." This would mean 1918 was the last time Boston won a world series. In reality, they have since won in 2004, 2007, and 2013. (This could be a reference to the Curse of the Bambino, which in reality was broken in 2004.) The article also makes reference to ways Boston has previously lost their chance to win. The line "[lost by a] ball that rolls disastrously through an infielder's legs," is a clear reference to the nature of the error made by Boston first baseman Bill Buckner that allowed the New York Mets to win Game 6 of the 1986 World Series (and eventually the whole series) over Boston when the Red Sox were one strike away from winning the game and the championship.
The baseball cap and uniform have a red-and-white color scheme, suggesting the Red Sox departed from their traditional red and navy blue uniforms. Furthermore, batting helmets found throughout the Commonwealth are royal blue.
Boston's opponent in the 2077 World Series is mentioned in the game as 'Texas'. This suggests the Texas Rangers, but it makes no sense with current timeline teams because both the Rangers and the Red Sox are American League teams and would not be facing each other in the World Series. (It's possible that the opponent was meant to be the Houston Astros, but this team is commonly referred to as 'Houston' to differentiate it from the Rangers. Not only that, but the Astros are also currently an American League team, giving the same problem. This could be remedied when one considers that until 2013 the Astros were a National League team. It is also possible the divergence includes a new team being designated 'Texas' or that the Rangers moved to the National League.)
The schedule of the World Series also suggests a possible divergence from modern baseball. The fourth game of the 2077 World Series is scheduled for October 23rd. The length needed for the playoffs (as well as possible delays due to weather, etc.) means the first game of the World Series usually begins after October 20th and can easily continue into November before being definitively won. A World Series being resolved by October 23rd is technically possible, but unlikely. A possible explanation is that there may be less than 30 teams and therefore a shorter playoff series, or that the playoffs are organized differently. It is also possible the playoffs proceeded exceptionally quickly that year.
Finally, given that the baseball card of Matt "The Missile" Murtagh includes batting statistics when he is a pitcher, it suggests that the Designated Hitter rule was never implemented in Fallout's version of the American League, or at least it was eventually rescinded before 2077. More likely this is a mistake as the stats listed on his baseball card appear more akin to a position player's than a pitcher's. (Very vaguely, as the text is so small.)
- ↑ In the Cabot House terminal entries, the transistor is mentioned in an entry that dates to 2023
- ↑ Economy of Pittsburgh on Wikipedia Once the center of the American steel industry, and still known as "The Steel City", today the city of Pittsburgh has no steel mills within its limits, though Pittsburgh-based companies such as US Steel, Ampco Pittsburgh and Allegheny Technologies own several working mills in the Pittsburgh metropolitan area.]
- ↑ Experimental Treatments for Radiation Poisoning
- ↑ Newscaster