Tag Archives: Weird (Pseudo)science

Hypothesis: Our civilization, and any other civilization that will ever come into contact with us, will never invent backwards time travel. . .

. . . Because if it did, then time travelers would have infiltrated our past and present.

Instapundit’s periodic musings on the subject get us thinking about this.


1. Our present is so insignificant that no future time traveler would bother to visit us. If time travel is invented thousands of years in the future, is it possible that our current civilization, from its beginnings until today, poses no interest, especially for a one-way trip?

2. There will be rules—based on civilization’s advanced, perhaps complete, understanding of relativity and quantum mechanics—and time travelers will be very careful not to make their presence known. Perhaps time travelers have already influenced our present, but we don’t know it, because each such an occurrence would create a divergence into a parallel universe. But wouldn’t they have left a trace in a more pedestrian way, such as someone appearing out of the blue, getting rich outside the bounds of believability by “predicting” the stock market, leaving behind some object that we cannot explain, or otherwise altering the course of observed events in a way that we could not explain scientifically? Assuming that backwards time travel is invented in the future, then it’s reasonable to assume that, sometime afterward, it would become widespread, leading to the likelihood of abuse. Or maybe our future is a totalitarian dystopia, in which a small band of elites controls all significant technology, and becomes adept at navigating through time to achieve its objectives without a footprint. Paradoxically, such elites would practically be gods, and perhaps they would then have no motivation to interfere much with the past anyway.

It is at least conceivable that time travelers have affected our world and we don’t know it. But what about paradoxes—what if a time traveler traveled back in time and killed the inventor of the time machine, or Einstein before he formulated the theory of relativity, or the traveler’s own parents when they were children? We have no way to comprehend the impact of such a paradox. Which leads to our final counterargument. . .

3. Perhaps backward time travel will be invented in the future, but it will destroy our civilization, sometime after the present. We cannot imagine the social, political, and economic environment that must be prevalent in a society in which backwards time travel were widely available. But surely those conditions would post existential risk to the civilization.

Maybe backwards time travel would be possible if, and perhaps only if, we were living in a computer simulation. Our programmers, who would have nearly infinite intelligence to foresee all possible implications simultaneously and thus to mitigate any uncertainty, would make sure that everything worked out and space-time remained stable. But then that wouldn’t really be backwards time travel in a universal sense.

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Greek island where “people forget to die”: Looks a lot like a predictable statistical anomaly

A story in the New York Times, “The Island Where People Forget to Die,” marvels at how the population (673 souls) of Ikaria, a Greek island in the Aegean, seem to live for a long time.

The story refers to research by two scholars, Gianni Pes of the University of Sassari in Italy and Michel Poulain of Belgium, who have conducted anecdotal research on population clusters with a disproportionate number of people who live a long time.  Their list of anomalous communities is comprised, in addition to Ikaria, of:

  • “on Costa Rica’s Nicoya Peninsula, we discovered a population of 100,000 mestizos with a lower-than-normal rate of middle-age mortality.”
  • “in Loma Linda, Calif., we identified a population of Seventh-day Adventists in which most of the adherents’ life expectancy exceeded the American average by about a decade.”
  • “a region of Sardinia’s Nuoro province as the place with the highest concentration of male centenarians in the world.”

For Ikaria, people tend to live a long time, and the protaganist of the story moved there after being diagnosed with cancer in 1976, but it went into remission and he is still alive.  Bless him.

Do you see the problem here?  If one slices and dices the world population of seven billion enough ways—the cited researchers’ clusters include one ethnic group, a religious group, a regional group, and an island—then one will find outliers.  Similarly, if one adopts enough different measures of longevity—in this case, middle-age mortality, life expectancy, prevalence of centenarians, and, in Ikaria, rates of people who reach 90—then one will surely find a few that emerge as outliers.  (Not to mention the small sample size in this case.)

Out of the practically infinite number of semi-coherent groupings of people and semi-coherent measures of longevity, by definition, there will be a few that fall into the 0.01%, or 0.0001%, tail of the distribution.  It’s as if you toss a coin 1,000,000 times and search the results for a string of ten consecutive heads and, finding it, you say, “ah-ha—this coin is biased!”  In fact, you expect to get ten consecutive heads about once in every 1,000 ten-toss experiments.

We can hope that Drs. Pes and Poulain consider this inferential reality in their research, but the article does not even address this obvious potential rejoinder.

By the way, the article cites several plausible reasons for longevity in Ikaria:  the island’s hot springs; the relaxed lifestyle there*; a sense of community; a healthy diet, including vegetables, wine, and olive oil; exercise, since the area is rural and hilly; and the popular local drink of tea made from local herbs.  These factors make Ikaria seem like a nice place to live — and no doubt these factors contribute at a basic level to longevity—but they are hardly so novel as to paint this case study as extraordinary.

*Unemployment on the island is 40%.

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