this post was submitted on 01 Dec 2023
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[โ€“] [email protected] 123 points 11 months ago* (last edited 11 months ago) (5 children)

The pocket of air that was where you teleported now get displaced at a very decent fraction of the speed of light while the pocket of space you once ocupied becomes a almost pure vaccum. the air moves so fast it creates a sonic boom that ruptures the ear drums. Then, a few atoms of air collide together with such incredible force the atoms split and causes a small grade nuclear explosion.

[โ€“] [email protected] 75 points 11 months ago* (last edited 11 months ago) (4 children)

Assuming

  • cylindrical human, 2m tall, 25 cm diameter.
  • air displaced from the point you teleport to is instantly moved to form a monolayer (1 molecule thick) on your surface.
  • The displacement of air is adiabatic (no heat is transferred, which will be true if the displacement is instantaneous)

Volume of displaced air: โ‰ˆ 100L = 0.1m^3 At atmospheric conditions: โ‰ˆ 4 mol

Surface area of cylindrical human: โ‰ˆ 1.58 m^2 Diameter of nitrogen molecule (which is roughly the same as for an oxygen molecule) : โ‰ˆ 3 ร… Volume of monolayer: โ‰ˆ 4.7e-10 m^3

Treating the air as an ideal gas (terrible approximation for this process) gives us a post-compression pressure of โ‰ˆ 45 PPa (you read that right: Peta-pascal) or 450 Gbar, and a temperature of roughly 650 000 K.

These conditions are definitely in the range where fusion might be possible (see: solar conditions). So to the people saying you are only "trying to science", I would say I agree with your initial assessment.

I'm on my phone now, but I can run the numbers using something more accurate than ideal gas when I get my computer. However, this is so extreme that I don't really think it will change anything.

Edit: We'll just look at how densely packed the monolayer is. Our cylindrical person has an area of 1.58 m^2, which, assuming an optimally packed monolayer gives us about 48 micro ร…^2 per particle, or an average inter-particle distance of about 3.9 milli ร…. For reference, that means the average distance between molecules is about 0.1 % of the diameter of the molecules (roughly 3 ร…) I think we can safely say that fusion is a possible or even likely outcome of this procedure.

[โ€“] [email protected] 48 points 11 months ago (2 children)

Surface area of cylindrical human

How to spot a mathematician/physicist.

[โ€“] [email protected] 17 points 11 months ago* (last edited 9 months ago)

I'm actually a chemist, thankyouverymuch

#Chemistry Is When There's Too Many Electrons For The Physicists

;)

[โ€“] [email protected] 5 points 11 months ago* (last edited 11 months ago) (1 children)

I feel like a mathematician would go a step further and not even assume a specific geometry. Maybe a human is just a subset of points in a measure space, with a measure fixed at 1 human-unit.

[โ€“] [email protected] 1 points 11 months ago (1 children)

To be fair, the result of this calculation only depends on the area/volume ratio of the human. I used the specific cylinder, because humans are roughly cylindrical, and have a volume of roughly 100 L. The surface area of a regular human is probably a bit larger than that of a cylindrical one though.

[โ€“] [email protected] 2 points 11 months ago* (last edited 11 months ago)

That's true, and in this case where the layer is a single molecule thick, pores and even cellular structure will add to it quite a bit. Hell, at that scale it's probably hard to define any solid boundary to the body at all, since you'll have things like the surface of evaporating sweat. Once again, we need to know a bit more about how the magic works to give a single answer.

Our mathematician would have to add a measure on subset boundaries I guess. Or maybe just hand the problem off to a big boy who can handle things in the real world (zing!).

[โ€“] [email protected] 10 points 11 months ago

Can confirm, as a cylindrical human, 2m tall, 25 cm diameter.

[โ€“] [email protected] 9 points 11 months ago

Thank you for taking the time to do the actual calculations, you are a legend!

[โ€“] [email protected] 2 points 11 months ago

Oh, you're assuming a monolayer. Yeah, you're right then. I thought you were talking about the vacuum end and the air was magic-ed out in a more orderly fashion at the other end.

[โ€“] [email protected] 27 points 11 months ago (2 children)
[โ€“] [email protected] 14 points 11 months ago* (last edited 11 months ago) (2 children)

I mean, no. That's not enough energy to cause nuclear stuff. This guy tried sciencing, which I still respect in the context of a goofy scenario, I guess.

[โ€“] [email protected] 16 points 11 months ago (1 children)

The math actually says that we might quite possibly get nuclear stuff. I checked because at first I intuitively thought the same thing as you.

[โ€“] [email protected] 4 points 11 months ago* (last edited 11 months ago) (1 children)

Wouldn't that mean opening an evacuated tube should produce a flash of radiation, and supersonic planes should absolutely glow? I'm skeptical.

[โ€“] [email protected] 11 points 11 months ago* (last edited 11 months ago) (2 children)

Air moves as fast as the potential difference in pressure between where it is and where it wants to go. Also pressure has a direct relationship with heat as in the more under pressure a volume of air is the more hot it becomes.

The potential difference between regular earth or spaceship atmospheric pressure and vaccum is relatively little so air flow is only subsonic when evacuated vaccum tubes break and exposed to normal atmosphere conditions.

However if you go to the bottom of the ocean the pressure there is enough to cause implosions which create a kind of under water sonic boom as well as light radiation as the water rushes in to the vaccum faster than the speed of sound. The mantis shrimp even evolved this as a kind of defense by snapping its claws so fast it creates vaccum bubbles that implode which creates powerful shockwaves while producing light. Here's a great video about that

I dont know enough about aerodynamics to know about why supersonic planes dont glow. Maybe they do and its just in infrared. Hopefully someone else can chime in.

Still that's almost nothing compared to the pressures created around the body in this scenario which as the person calculated is surface-of-the-sun levels of pressure being instantly pushed on earthy atmosphere molecules. The forces created by the potential difference in pressure in this scenario could theoretically be enough to overcome the strong nuclear force binding the nucleus of air atoms.

[โ€“] [email protected] 2 points 11 months ago (1 children)

The difference I see with supersonic jets is that our hypothetical scenario is all about an instantaneous occurrence, whereas jets start at a standstill and accelerate up to that speed relatively gradually, meaning there is some opportunity for air displacement to begin before the jet arrives and occur over some marginally longer time period.

[โ€“] [email protected] 3 points 11 months ago

That seems like a reasonable hypothesis, thanks for the input!

[โ€“] [email protected] 1 points 11 months ago

Oh, so you're assuming all the air is instantly pushed to the person's skin? Yeah, that could do it. Actually, if the stuff is pushed arbitrarily close together you get black holes. I read OP as the destination air gets moved out more evenly, and just the vacuum remains.

Supersonic planes do get hot, because the air basically heats until the flow is subsonic again, so they would glow in the infrared a bit. Normal atmospheric pressure, as you noted, isn't enough to make anything nuclear or even chemical happen.

[โ€“] [email protected] 6 points 11 months ago (2 children)

Your atoms now occupy the same space as the air atoms. How exactly is this not going to result in nuclear tomfoolery?

[โ€“] [email protected] 4 points 11 months ago

That might do it, if they really land on top of each other. OP said it was air molecules colliding with each other in the shock, though.

[โ€“] [email protected] 2 points 11 months ago (1 children)

Depends on what teleportation technology we're using. I think a lot of us assume that when you're teleported you're quickly assembled atom by atom and don't simply instantly exist in a new location.

[โ€“] [email protected] 3 points 11 months ago

There's a few questions here. At the atomic level, quantum mechanics comes into play, and instant change basically breaks it, so you'd expect it to be slightly gradual somehow.

[โ€“] [email protected] 3 points 11 months ago

Nah, just reads too much XKCD.

[โ€“] [email protected] 11 points 11 months ago

I assume it's a switcharoo scenario. Otherwise where does the air in my new location go?

[โ€“] [email protected] 2 points 11 months ago

I'm wet and sitting on the tile floor. I'm cold :(

[โ€“] [email protected] 2 points 11 months ago (1 children)

Why would air displace so quickly?

[โ€“] [email protected] 5 points 11 months ago* (last edited 11 months ago) (1 children)

Instantly moving any kind of mass in the context of physics means moving it super close to the speed of light (well actually, it would have to be faster than the speed of light for truely instant which opens up a can of worms all its own so lets just say really really close to instant, as close as the universe lets you get without inviting FTL time paradoxes) which would impart insane amounts of momentum energy that has to transfer to the air it pushes.

That supercharged almost-speed-of-light air needs to go somewhere (unless were talking about the kind of teleportation where atoms get transposed into each other in which you just skip to the nuke step).

[โ€“] [email protected] 3 points 11 months ago (1 children)

It would still have to repel the air with electromagnetic forces between electrons, so the total speed is still limited. Or does the air just stay in place inside your body? If not, then the teleporter would have to move the air somewhere.