NAP's random Science & Technology thread

[NotAPretender]

And on the other hand: This is closer to my simple thought regarding Extraterrestrial civilizations and I've concluded that the author is a debbie downer and a loser and a not much better writer than he is a scientist. The first property of the scientist author sucks and the second is forgivable ... put together he is off my Christmas list.

The celebrated physicist alan Guth has presented a rather different cosmological argument to show we are alone. The argument is based on one of the key underpinning concepts in cosmology: inflation. Guth and others came up with the concept of inflation during the 1980s in order to explain several observed features of the universe that are puzzles within the traditional Big Bang picture. The basic idea is that the universe began as a sort of vacuum fluctuation, a small patch of spacetime that underwent a brief period of exponential expansion---inflation---that took it almost instantaneously from a subnuclear-sized object to an object the size of an apple. Once inflation stopped, the "traditional" Big Bang expansionary phase took over, Inflation explains how the universe got to be so big, so smooth, so flat. In addition to explaining these observations (and various other properties of the universe), inflation strongly suggests that our universe is part of a multiverse---there are an infinite number of "local universes" or "bubble universes", of which ours is just one. In the particular bubble universe we inhabit the inflationary expansion ceased after a tiny fraction of a second; in other regions of this vast landscape the expansion continues, spawning bubble universes as it does so. In other words, once inflation starts it never stops; it's eternal.

There are many different specific models of inflation, but it's difficult to avoid the general conclusion that eternal inflation creates vast numbers of universes. Guth considers one model in which there are good reasons to suppose that every second the number of bubble universes is multiplied by a factor of e raised to 10³⁷--a number that makes the googol look vanishingly small. This is an insanely large rate of universe production: you start with one universe, a second later there are e raised to 10³⁷ universes, and a second after that you have to multiply by the same factor. It boggles the mind, but it's the sort of picture one has to contemplate when discussing cosmological inflation. And in this picture, young universes vastly outnumber old universes. Assuming this scenario holds true, Guth Poses the question: is there another civilization in the visible universe (that is, the bubble universe we inhabit) that's as advance as ours?

Suppose it takes a definit minimum time t_civ to develop an advanced civilization. (It doesn't doesn't really matter how we define "advanced" here; equally, although a sharp minimum development time is unlikely to be realistic, we don't have to define a more convincing measure. The numbers involved outweigh these considerations.) Since we exist, the age t₀ of our bubble universe must satisfy the constraint t₀> t_civ. Now suppose an ETC exists somewhere in our bubble universe, and that it's one second more advanced than us. Our bubble universe would then also have to satisfy the constraint t₀> t_civ + 1s. However, in the scenario we are considering, there are e raised to 10³⁷ more bubble universes that satisfy the first constraint than satisfy the second constraint. Since we know we live in a bubble universe that satisfies t₀> t_civ we are overwhelmingly unlikely to find that our bubble universe also satisfies t₀> t_civ + 1s. The conclusion is that we are alone in our own particular part of the multiverse.

Guth wryly points out that although this argument might explain the Fermi paradox, a more plausible interpretation is that we don't fully understand how the formulate probabilities when discussing the infinity of bubble universes that arise in eternal inflation.

The cosmology-based argument of Alan Guth suggests that there might be infinitely many ETCs in the wider universe, but none whith which we can communicate. Effectively, we are alone.

[NotAPretender]

Listen to this video and then start listening to the conspiracy theorists. The other day I read one poor sap on PA state that the people like them were going to save the world. So far their plan is not working but then a lot of mental energy is expended trying to track the tentacle endings of the latest plot to defeat them.

Source: https://www.youtube.com/watch?v=knxt8vV6eAM

[NotAPretender]

This is excellent. A presentation of one of the pre-eminent genetics scientists, Svaante Paabo. He has a very good explanation of risk factors and how they relate to blood types and Neanderthal genes. I think Aragorn this explores the factors that you mentioned sometime back.

Source: https://www.youtube.com/watch?v=MnCuTJ1NMfc

[NotAPretender]

Chromosome 3, if someone has the Neanderthal gene variant and they get sick they die ...

[NotAPretender]

There have in geological times been 5 major extinctions: Ordovician, Devonian, Permian, Triassic and Cretaceous. There is one more actually that doesn’t get much attention and it is called the Holocene.

The Holocene Extinction

It would be wrong to discuss past mass-extinction events without mentioning the Holocene extinction. The Holocene epoch encompasses the last 10 millennia up to the present day. In other words, we’re living through a mass-extinction event. In this case the cause is clear: human activity. We hunt species to extinction; we cause havoc by introducing alien species into ecosystems; and, most importantly, we destroy habitats. It doesn’t feel as if we’re in the midst of a mass-extinction because, on an individual scale, 10,000 years is a long time. On a geological scale, though, it is an instant. Under some estimates, the rate at which species are becoming extinct is now 120,000 times the “normal” or “background” rate. Many of the species made extinct by our destruction of rain forests have never even been documented. If the current rate of extinction is maintained, and the destruction of the rain forests continues, then global atmospheric and climate effects seem certain to occur. It’s then quite possible that ours will be one of the species that joins the extinction. Harking back to a previous solution discussed in the book, perhaps a general evolutionary law is that intelligence extinguishes itself.

- Stephen Webb - “Seventy-Five Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life”

Source: https://www.youtube.com/watch?v=wissIOikrqc

[NotAPretender]

I read today that there is a Neandertal gene variant on Chromosome 12 originating in Croatia ... I have some DNA from that region. So maybe 23andMe was correct. Which means some Neandertals might have survived Covid-19 after all. I hate being almost wrong.

Actually about a total of 24% which is more than I realized.

[Octopus Garden]

I hate being almost wrong.

Actually about a total of 24% which is more than I realized. NAP

i had an independent research team calculate how often I am wrong and they assessed me at 50%. So, you are doing pretty well!

Newish topic

The Sorcerers Apprentice

The Promise and Perils of AI

[I]If I could go back in time 700 years with my smart phone, awestruck medieval villagers might worship me as a god or kill me as a devil. But with no connectivity and a dead battery, my digital pacifier might look like a piece of obsidian jewelry in the hands of some bizarrely-dressed foreigner. ‘Hey Theodoric, let’s just be on the safe side and kill this weirdo.’

https://geoffolson.substack.com/p/the-sorcerers-apprentice-part-1

[NotAPretender]

Source: https://www.youtube.com/watch?v=v90mFCSOHQs

[Elen]

Interesting observations

[NotAPretender]

yeah ...

[NotAPretender]

This is interesting because it has serious ramifications for human health and space travel. They might be the key to long term missions and also be a very valuable influence on the human animal in general. Potentially a true breakthrough. This provides some clarification on what is common knowledge:

Source: https://www.youtube.com/watch?v=t7NdYxdUyYQ

[Elen]

Well...there's a survivor of hard conditions...except for the pleasant ones.

[NotAPretender]

Despite our ability to manipulate our realities with belief, will, magic, prayer, psychic intuition the hard real real is below. It is a good base point to start to determine the logic of any situation. Simply being aware that such a process exists should give us pause before we conclude anything and we should also realize that historical evidence is very important, as well.

If you estimated the probability to be between 70%-80% you’re in good company. Study after study shows that when doctors are given this problem (with the language of breast cancer and mammogram replacing the language of aliens and shapeshifter-detecting apps) about 6 in 7 of them give an estimate in the 70%-80% range. The correct answer is 7.76%. In other words, even though the accuracy of the test is 80% a positive test result means only 7.76% chance of the individual being an alien (or of having breast cancer, if the problem si couched in that language). If you want to see how the numbers stack up, the below applies the Bayes formula with the numbers given in the scenario.

Bayes and the Shapeshifter Problem:

Bayes’ theorem:

This is one of the most important equations in science.
P(H|E = P(E|H)P(H) / P(E)

• P(H|E) is called posterior probability of a hypothesis given some evidence.
• P(H) is prior probability based on evidence
• P(E|H) is the likelihood of the event without consideration of circumstances
• P(E) is the probability or (value) of the evidence

We want to know P(H|E)—the probability of the the alien shapeshifter hypothesis being true given the evidence of a positive test result.

What we are told is the likelihood P(E|H)—the probability of a positive test occurring given the individual is an alien, which in this case is 80%. Bayes tells us that we also need to take into account P(H), which is the chance that an individual chosen at random is an alien—1% in this case. Furthermore we also need to take into account P(E), which is the chance of getting any positive test—either a real positive or a false positive, in this case the chance of a real positive is 1% x 80% (aliens times accuracy) or 0.008. The chance of a false positive is 99% x 9.6%. (not aliens times fake aliens ‘humans’) most of them can actually be found on the internet (me) or, in other words, 0.09504). So P(E) = 0.008 + 0.09504 or 0.10304.
After applying the Bayes formula we see the result of P(H|E) is 7.76%