A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.
Rules
This is a science community. We use the Dawkins definition of meme.
Fewer than 50% of the cells in "your body" contain your own DNA.
There are many more bacteria, since they are much much smaller than "your own" eukaryotic cells.
Where you end and your "gut flora" begin and end is not as clear as you might first believe.
he would have to snap his fingers infinitely many times to kill everyone so he is not that powerful
That’s an interesting question as to whether the infinity gauntlet rounds down.
Like, if there were 3 survivors of a species and thanos snapped the universe, does the gauntlet round up to 2 survivors, or down to one?
I thought it was just an instantaneous, every living thing has a 50/50 chance of living or dying. No rounding, no species specific exceptions.
or down to one and a half?
The snap was always the dumbest part of the entire avenger series. Let's say for example, you have a bunch of deer that are eating the forest bare, so you let hunters kill half of them... Then what happens next? You have the exact same problem in a few years. The snap solves nothing.
Also if you can snap your fingers and do this, why can't you snap your fingers and make twice the food supply?
The snap is just stupid, even in a world made-up physics-defying superheroes.
To be fair, it made slightly more sense in the comics, though still batshit. In the comics there was no noble purpose like they tried to shoehorn in for the MCU. IIRC, Thanos was literally doing it to impressed Death (the cosmic entity) to gain her affection.
Even worse than that. 50% of all life dies, right? That's 50% of the plants too. If you know anything about food chains, taking 50% of everything leaves the top of the chain massively overloaded.
It's stupid only because they try to rationalize it.
Comics Thanos just wants to commit genocide so his crush notices him. That's also stupid, but he's a big purple space alien so what can you expect? Using a magic space glove powered by stardust and wishfish to kill half of all life as an incredible gesture of his devotion to Death makes internal sense.
His crush is literally Death, so it kinda makes sense that genocide would be the way to get her attention.
It's bullshit space magic, it probably considers what Thanos thinks of as life. Why it snapped the birds is a different plot hole altogether, because it means he snapped away half the food, too.
If surviving humans lost 50% of their gut bacteria, that means that those snapped away left 50% of their gut bacteria behind.
More gut bacteria for the rest of us, that's what I say!
Yeah but I thought about this I realized that whenever somebody vanished from the snap it would leave behind a slurry of gut microbes and a (different looking) dust from all of the skin mites, microbes, and stuff that just live all over the human body. Meaning the aftermath would have been even messier.
Maybe that's exactly what the dust was.
Then it should have been goopier lol
That's not how it worked. He killed 50% of gut bacteria by killing 50% of the hosts.
Depends on whether "50% of all life" means half of the contiguous lumps of cells we call "creatures" or simply half of all living matter.
You literally see individual people dissolving, and others being unaffected. How is this unclear?
or 100% of the 50% that are destroyed are the gut bacteria in the humans etc that got snapped
The alternative is even more disturbing: snapped humans leave behind a cloud of poopy gut microbes.
In reality, since it was more random, some poor soul would have their whole biomes destroyed, and just be rekd.
That would be incredibly unlikely. Due to the huge number of gut microbes, the chance to even lose 5% off of the median, even with billions of trials, is functionally zero.
Maybe in your gut biome, but mine is just two or three really, really large bacteria
To expand a little:
For a much smaller sample size of just 1 million, the probability to lose just 1% off of the median is basically zero.
WolframAlpha doesn't even bother to calculate the exact result and just rounds it:
https://www.wolframalpha.com/input?i=P%5B490000+%3C+X+%3C+510000%5D+for+X%7EB%281000000%2C0.5%29
Yeah, I was trying to compute the "ballpark" of the odds, but it's actually hard to do because of how astronomically improbable it is. Even computation systems that are designed to compute rather big/small numbers (think 100,000,000^1,000,000 big) fail.
Here's another example: If a human only had 1,000 gut microbes, the chance that over 900 of them get snapped is 1 in ~10^162 [WA]. (This was roughly the biggest number I could get WA to yield a non-zero answer for a >90% snap.)
Now if you do that for every human on earth, the probability is still essentially zero. [WA]
When you consider that humans don't have 1000 gut microbes, they have over 10 trillion, it's just mind bogglingly improbable.
I've found a proper approximation after some time and some searching.
Since the binomial distribution has a very large n, we can use the central limit theorem and treat it as a normal distribution. The mean would be obviously 500 billion, the standard deviation is √(n * p * (1-p)) which results in 500,000.
You still cannot plug that into WA unfortunately so we have to use a workaround.
You would calculate it manually through:
Φ(b) - Φ(a), with
b = (510 billion - mean) / (standard deviation) = 20,000
and
a = (490 billion - mean) / (standard deviation) = -20,000
and
Φ(x) = 0.5 * (1 + erf(x/√2))
erf(x) is the error function which has the neat property: erf(-x) = -erf(x)
You could replace erf(x) with an integral but this would be illegible without LaTeX.
Therefore:
Φ(20,000) - Φ(-20,000)
= 0.5 * [ erf(20,000/√2) - erf(-20,000/√2) ]
= erf(20,000/√2)
≈ erf(14,142)
WolframAlpha will unfortunately not calculate this either.
However, according to Wikipedia an approximation exists which shows that:
1 - erf(x) ≈ [(1 - e^(-Ax))e^(-x²)] / (Bx√π)
And apparently A = 1.98 and B = 1.135 give good approximations for all x≥0.
After failing to get a proper approximation from WA again and having to calculate every part by itself, the result is very roughly around 1 - 10^(-86,857,234).
So it is very safe to assume you will lose between 49% and 51% of your gut bacteria. For a more realistic 10 trillion you should replace a and b above with around ±63,200 but I don't want to bother calculating the rest and having WolframAlpha tell me my intermediary steps are equal to zero.
Whoa, good work! I think I'm going to have to go over this a few times to grock how it works, especially the Φ(b) - Φ(a) bit. My stats textbook has a bit too much dust on it. ;)
Losing 50% of your gut bioma will be fixed in an hour or two.
Yeah, yeast doubling rate is around 90 mins in optimal conditions, I would assume the rest of the microbes in your gut would have a very similar rate and they would be well adapted to those conditions.
So will bacteriophages and viruses be snapped as well? Does it mean that scientists can utilize the Thanos snap to determine for good whether viruses are alive?
The snap must take intention into account, like a genie, and not the literal wording of the wish, like a monkey's paw, because otherwise everyone in the universe would have just been cut in half.
But also: what if Thanos himself got snapped out, along with the power glove (because for some reason it turned their clothes into dust, too)? The heroes would have been fucked, right? It's been a minute since I saw the movies but IIRC, they used the time stone to go back in time. But what if the stone was gone because it was part of Thanos' attire? He himself used the stones to destroy the stones, so there is probably a timeline where he got snapped away with everyone else, destroying the stones in the process.
The stones were destroyed before the remaining Avengers found Thanos. That's why they went back in time. And they needed Tony not to be killed by the snap (hence Strange's bargain) so that he could invent time travel without relying on the time stone.