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A Study Shows There’s a 50% Chance We’re Living in a Simulation

Photo credit: Yagi Studio - Getty Images
Photo credit: Yagi Studio – Getty Images

From Popular Mechanics

If real life in 2020 seems like just too much, take comfort in some breaking news: scientists say odds are even that we’re living in a simulation. The coin flip depends a great deal on science we may uncover in the near future, they say.

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The 50/50 probability is rounded from a calculation whose outcome is more like 50.22222 to 49.77778. Scientific American cites the landmark 2003 paper “Are We Living in a Computer Simulation?” by philosopher Nick Bostrom. It’s worth reading Bostrom’s brief abstract in full:

“I argue that at least one of the following propositions is true: (1) the human species is very likely to become extinct before reaching a ‘posthuman’ stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of its evolutionary history (or variations thereof); (3) we are almost certainly living in a computer simulation. It follows that the belief that there is a significant chance that we shall one day become posthumans who run ancestor‐simulations is false, unless we are currently living in a simulation. I discuss some consequences of this result.”

Scientific American points out that The Matrix and its sequels did a lot to push the simulation theory forward, but philosophers have speculated in this direction for thousands of years. There are also many theories that flirt with simulation in the guise of radical solipsism and skepticism.

But Bostrom’s simulation theory in particular pivots on computing power. It doesn’t have to be supercomputers the way we imagine them today—think of proposed galaxy-scale superstructures like Dyson spheres, or even the imaginings of Star Trek writers. If a computer existed that could hold our entire universe inside, we likely wouldn’t recognize its workings.

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Bostrom’s claim is both philosophically and probabilistically bold, with considered outcomes he has placed almost on a pure binary. This led Columbia University astronomer David Kipping to run his own numbers using Bostrom’s argument as a guide.

Kipping began with Bayesian analysis, which lets the calculator include assumptions as a way to aid in the modeling. And since Bostrom’s first two criteria both posit there is no simulation, he condensed them into one criterion. Then, Scientific American explains, Kipping assigned “the principle of indifference,” which is the most nonspecific and non-assumptive “prior probability” you can use.

The next part requires a bit of a deep breath.

“Kipping then showed that even in the simulation hypothesis, most of the simulated realities would be nulliparous,” Scientific American‘s Anil Ananthaswamy writes, meaning the simulations cannot spawn their own additional simulations. He continues:

“That is because as simulations spawn more simulations, the computing resources available to each subsequent generation dwindles to the point where the vast majority of realities will be those that do not have the computing power necessary to simulate offspring realities that are capable

Study shows how climate impacts food webs, poses socioeconomic threat in Eastern Africa

Study shows how climate impacts food webs, poses socioeconomic threat in Eastern Africa
The research team spent 12 days on Lake Tanganyika collecting core samples from the lake’s floor. They chartered a Congolese merchant vessel, seen here, and adapted it for their research project. Credit: Michael McGlue, University of Kentucky

A new study is sounding the alarm on the impact climate change could have on one of the world’s most vulnerable regions.


Michael McGlue, Pioneer Natural Resources Professor of Stratigraphy in the University of Kentucky Department of Earth and Environmental Sciences, and his team conducted the study at Lake Tanganyika—a major African fishery. The results, which published today in Science Advances, show how certain changes in climate may place the fishery at risk, potentially diminishing food resources for millions of people in this area of eastern Africa.

“Lake Tanganyika’s fish are a critically important resource for impoverished people from four nations (Tanzania, Democratic Republic of the Congo, Burundi and Zambia) and resilience to environmental change in that region is quite low,” McGlue said. “Our study revealed that high frequency variability in climate can lead to major disruptions in how the lake’s food web functions.”

Small pelagic fish, known locally as dagaa, are abundant in Lake Tanganyika, and their conservation is pivotal to the food security and economy of rapidly growing and largely impoverished segments of these four nations.

Dagaa feed on algae and plankton, which means greater algae production in the lake results in more fish. How this aquatic food web responds to external forces, like climate, is critical for identifying vulnerabilities and maintaining healthy fish stocks. But until now, very limited information existed on how Lake Tanganyika may respond to such forces.

To understand how the lake reacts to climate changes, the team would need detailed information on the lake’s upwelling—the process by which deep waters rise and fertilize surface waters, thereby increasing algae and photosynthesis. In order to observe this, the team would have to obtain data from well-preserved sediment cores within the lake.

McGlue and his team traveled to one of the most remote regions of Lake Tanganyika, the southern basin, on a 12-day trip to collect these cores from the lake floor.

“The winds were especially violent that season, so most of our cruise was spent taking refuge from the waves in bays near the shoreline,” McGlue said. “But in the narrow window when the winds dropped, we raced out to our stations and collected the cores.”

McGlue and his team would later “read” the layers of sediment.

“The chemistry and fossil content of each layer tells us a specific story about how the lake functions,” McGlue said. “Limnologists (scientists who study the lake today, like our co-author Dr. Ismael Kimirei) help us to translate the information in the sedimentary record and learn how climate change affects the lake’s food web.”

Until now, sedimentary records from Lake Tanganyika lacked the resolution needed to accurately measure the influence of frequent climatic events, such as the El Nino Southern Oscillation (ENSO). Most sedimentary datasets are low resolution, meaning that changes

Climate patterns linked in Amazon, North and South America, study shows

amazon rainforest
Credit: CC0 Public Domain

University of Arkansas researchers have established a link between climate patterns in the Amazon and large parts of North and South America using their newly developed tree-ring chronology from the Amazon River basin.


The discovery helps researchers better understand large-scale climate extremes and the impact of the El Niño phenomenon.

Tree growth is a well-established climate proxy. By comparing growth rings in Cedrela odorata trees found in the Rio Paru watershed of the eastern Amazon River with hundreds of similar chronologies in North and South America, scientists have shown an inverse relationship in tree growth, and therefore precipitation patterns, between the areas. Drought in the Amazon is correlated with wetness in the southwestern United States, Mexico and Patagonia, and vice versa.

The process is driven by the El Niño phenomenon, which influences surface-level winds along the equator, researchers said. El Niño is the name given to a large-scale irregularly occurring climate pattern associated with unusually warm water in the Pacific Ocean.

“The new Cedrela chronologies from the Amazon, when compared with the hundreds of tree-ring chronologies in temperate North and South America, document this Pan American resonance of climate and ecosystem extremes in the centuries before widespread deforestation or human-caused climate change,” said Dave Stahle, Distinguished Professor of geosciences and first author of a study documenting the findings in the journal Environmental Research Letters.

Credit: University of Arkansas

The connection was not documented until researchers at the University of Arkansas Tree Ring Laboratory, along with colleagues from Brazil and Argentina, developed rainfall reconstructions from growth rings in Cedrela trees. Most rainfall records in the Amazon only date back about 70 years, but Cedrelas live for 200 to 300 years, providing valuable rainfall proxies that pre-date human-influenced climate change. Their work in the Amazon is documented in a short video, and also on a dedicated web site.

In the past 40 years, drought and flood extremes have increased in the Amazon basin, the researchers noted, raising the question of whether human-induced climate change and deforestation are affecting Amazon climate. While that remains an open question, the longer Cedrela-based precipitation record indicates that periods of rainfall extremes occurred in the past and the current extremes might be partly due to natural climate rhythms.

The study will help researchers better understand an area of unequaled biodiversity. The Amazon is home to an estimated 16,000 species of trees and one-tenth of all known species found on the planet, Stahle noted. “The long climate history written in the growth rings of old Cedrela trees in Amazonia will surely be important to the sustainability of the biome.”


Study quantifies Saharan dust reaching Amazon


More information:
D W Stahle et al. Pan American interactions of Amazon precipitation, streamflow, and tree growth extremes, Environmental Research Letters (2020). DOI: 10.1088/1748-9326/ababc6
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University of Arkansas

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Climate patterns linked in Amazon, North and South America, study shows (2020, October 9)
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Biden Widens Electoral College Lead Over Trump as Projection Shows Arizona, New Hampshire Shift Blue

Democratic Presidential candidate Joe Biden has increased his Electoral College lead over President Donald Trump, as a projection map shows Arizona and New Hampshire shifting blue.

The projection map, named Sabato’s Crystal Ball is created by the University of Virginia’s Center for Politics, and the election race ratings “are based on a number of factors, including electoral history, polling, candidate quality, modeling, and reporting,” according to the map.

The map shows Electoral College changes for three key swing states, including Arizona, New Hampshire and Georgia. According to the map, Arizona moved from a “toss up” to “leans Democratic,” New Hampshire moved from “leans Democratic” to “likely Democratic” and Georgia went from “leans Republican” to a “toss up.”

According to Ballotpedia.org, during the 2016 election, Trump won Arizona by 3.6 points but lost New Hampshire to Hillary Clinton by 0.3 points.

The shift to blue in Arizona and New Hampshire push Biden past 270 electoral votes needed as well as increasing his lead over the Republican president.

According to the map, Biden and the Democrats are projected 290 electoral votes, with 13 states listed as “safe Democratic,” six states listed as “likely Democratic and five states as “lean Democratic.”

In comparison, the map shows Trump and the Republicans having 163 electoral votes, with 13 states listed as “safe Republican,” seven states listed as “likely Republican” and just one state listed as “lean Republican.”

The remaining five states, Iowa, Ohio, North Carolina, Georgia and Florida are listed as a toss-ups.

Joe Biden
Democratic presidential candidate Joe Biden, speaks to the press before boarding his campaign plane at Wilmington Airport on October 8 in New Castle, Delaware. The increase in Biden’s Electoral College lead over Trump comes within a month till Election Day.
Brendan Smialowski/Getty

Last week, the Crystal Ball Electoral College projection map showed Biden and the Democrats with 279 electoral votes, while Trump and the Republicans had 179. Eighty electoral votes were toss-ups.

The increase in Biden’s Electoral College lead over Trump comes within a month till Election Day, and recent polls have also shown his lead widening over the past few weeks.

Real Clear Politics has tracked the average of several nationally conducted polls and has indicated an increase in the former vice president’s advantage, as on September 18, he had an average lead of 5.8 points, but this has since increased to 9.7, in the most updated average.

Five Thirty Eight’s average of general election polls also shows Biden’s lead increasing as he led by an average of 7.6 points at the end of September but now leads by 9.8 points.

Two recent poll also show Biden ahead of Trump in Arizona and New Hampshire, the two swing states that shifted blue in the Crystal Ball projection map.

One poll conducted by Emerson College found Biden ahead of Trump by seven points in New Hampshire (52 to 45 percent) while a poll conducted by Reuters/IPSOS found the former vice president ahead by two points in Arizona (48 to 46 percent).

Newsweek