Random Science Question Thread!

[arus2001]

My curiosity tends to fall into line with how close we are to certain concepts we see in fiction. Like, when could we see...

- Projected images with tangible mass. (holodeck/force fields)
- Utilization of 3D printing for anything from food to transplant organs. (replicator-ish)
- Teleportation.
- Fully sensory immersive VR. (Matrix/anime death game of choice)
- Fully functional prosthetics. (React to brain signals, look real, etc.)
- Gene splicing. (So Gulk can get his catgirl girlfriend)
- FTL travel.

Like, I know some things like teleportation and warp tech are probably gonna remain a pipe dream, nevermind the more dilemma of whether or not teleporting literally kills/clones the target. Stuff like the Hatsune Miku dance/light shows indicate projection tech IS getting more elaborate. And I personally don't buy into the current VR trend since it's really just a pair of small TVs strapped to our head. Overall, I guess it's just stuff that's fun to imagine, but perhaps saddening when you realize we'll probably dead by the time some things do come about. Presuming we don't get hit by the Trumpocalypse.

Edit: I remember when I was younger an Parasite Eve came out. Was in 9th grade with a Biology class, so obviously when the game started pimping the idea that mitochondria could be manipulated to make people spontaneously combust and do other freaky things, I asked my teacher about it. Him being a smartass New Yorker, he just gave me that, "What the fuck is wrong with you?" look.

[Jaybar]

How long do the effects of an EMP last? Like, say a nuke went off in orbit, EMP etc. Everything affected by the EMP gets knocked out. Does stuff eventually come back or is it fried forever/until its fixed? I've always wondered

Depends on the orbit. Anything in low earth orbit like the ISS will decay slowly if it isn't boosted every so often, so if periodic firing of satellite rockets/thrusters are dependent on electronics then they will eventually decay and deorbit over time. Things that are beyond LEO will remain in orbit indefinitely until impacted by outside forces.

I don't know how recovery is done on objects like satellites but if they can become functional again after the EMP then they can survive once they are boosted into a stable orbit again assuming they haven't been off for more than a few days/weeks or whatever it takes to deorbit from their location. A highly eccentric orbit can survive very long as they only encounter the atmosphere at their perigree, thus only being affected briefly by atmospheric drag.

Kerbal Space Program scientist.

[Cail]

I was thinking more electronics here on earth, but thats still cool to know!

[Boyiee]

What would happen if a gamma ray burst skimmed or came close to earth and how close would it need to pass for it to be a problem (I'm assuming they are hot or something, turning air to plasma etc). Wouldn't we be able to see it coming or no?

[BerenTebogo]

continuing on my whacky worlds question, what would it be like if the force of gravity followed a different scale? for instance, what if gravity was about the same as it is now until you reached the size of the moon then leveled off dramatically, only increasing extremely slowly with mass? aka surface gravity on jupiter would only be very slightly more than the moon, and the gravity on the biggest known star would be about the same as earth. would this mean there would be no stars? or would everything just be dramatically bigger? aka earthlike planets the size of stars, and stars the size of a million of ours?

to best offthetopofhead physics, the universe would be a cold dead place. such a weak g-force wouldn't be enough to cause molecular gas clouds of sufficient size to collapse with resultant requisite pressure for star / galaxy formation.

Things to wiki cuz I'm on my phone: jeans mass / jeans radius

GMm/r^2 means Fg scales with masses of two interacting bodies. If there is a limit to Fg regardless of mass, large pockets of dust wouldnt collapse with the needed frequency (again I'm not even scratching this out on paper so I'm not answering in total absolutes, just grand scale).

[BerenTebogo]

My curiosity tends to fall into line with how close we are to certain concepts we see in fiction. Like, when could we see...

- Projected images with tangible mass. (holodeck/force fields)

This would mean that light (photons) could have mass. This is physically impossible.

- Utilization of 3D printing for anything from food to transplant organs. (replicator-ish)

Probably a decade or less in theory, due to ethics and laws maybe the rest of our lives for practice.

- Teleportation.

Physically impossible.

- Fully sensory immersive VR. (Matrix/anime death game of choice)

10-20 years.

- Fully functional prosthetics. (React to brain signals, look real, etc.)

10-20 years.

- Gene splicing. (So Gulk can get his catgirl girlfriend)

30 years ago. Eat a seedless watermelon.

- FTL travel.

Physically impossible.


Like, I know some things like teleportation and warp tech are probably gonna remain a pipe dream, nevermind the more dilemma of whether or not teleporting literally kills/clones the target. Stuff like the Hatsune Miku dance/light shows indicate projection tech IS getting more elaborate. And I personally don't buy into the current VR trend since it's really just a pair of small TVs strapped to our head. Overall, I guess it's just stuff that's fun to imagine, but perhaps saddening when you realize we'll probably dead by the time some things do come about. Presuming we don't get hit by the Trumpocalypse.

Edit: I remember when I was younger an Parasite Eve came out. Was in 9th grade with a Biology class, so obviously when the game started pimping the idea that mitochondria could be manipulated to make people spontaneously combust and do other freaky things, I asked my teacher about it. Him being a smartass New Yorker, he just gave me that, "What the fuck is wrong with you?" look.

Things you refer to as pipe dream need to be understood as "literally fucking impossible". It's not a question of "when" because the answer is "at the exact moment that penguinunicorns fucking elephant zombies takes over from dark energy as the dominant force of space-time expansion in our universe".

Edit: I am lazy and responded with years in the post I quoted. Read the quote part for answers.

[Boyiee]

On the topic of prosthetics, I want some ghost in the shell shit with Internet in my head because I was at the dentist getting a cleaning and I closed my eyes and wanted to watch that episode of ghost in the shell where the major robs the vault on the back of my eye lids but we can't do that yet.

[BerenTebogo]

What would happen if a gamma ray burst skimmed or came close to earth and how close would it need to pass for it to be a problem (I'm assuming they are hot or something, turning air to plasma etc). Wouldn't we be able to see it coming or no?

If one was pointed at us, and was close enough, we would be gone. Instantly. Bye.

It's not even "hot" it's the energy involved.

Near miss (i dont have a mile approximation here, sorry. Ask someone who works in high energy astrophysics...oh wait...) would strip the atmosphere and then we would be gone.

Part of my job involves reacting to and pointing a telescope at GRBs and sGRBs and for sGRB (the most energetic ones) we usually have 1-3 days to from a detection being triggered on a sky survey to being able to make any detection before the event has totally dimmed beyond useful science.

iirc (and I may not) sGRB emissions are on the order of < seconds and aren't repeated events. Neutron star being tidally disrupted by accretion onto black hole. The sGRB can be considered the equivalent of the juice squirting out when you bite on a grape.

[BerenTebogo]

On the topic of prosthetics, I want some ghost in the shell shit with Internet in my head because I was at the dentist getting a cleaning and I closed my eyes and wanted to watch that episode of ghost in the shell where the major robs the vault on the back of my eye lids but we can't do that yet.

BBC Horizon (documentary show) this past season did an episode about essentially how far we are from this. It is worth a watch.

Wiki bbc horizon episode list and look for most recent season - you'll know it when you see it. To rr en t able

[Boyiee]

But if its far as fuck away and pointed right at us it wouldn't take seconds to get here right doesn't it take light from stars a while to get here so couldn't one have happened and we are watching it come at us?

[BerenTebogo]

But if its far as fuck away and pointed right at us it wouldn't take seconds to get here right doesn't it take light from stars a while to get here so couldn't one have happened and we are watching it come at us?

Put it this way, next week the space telescope I work for is pointing some CCD cameras, which are some of the most delicate electronics you can conceive of, directly at one (because CCDs work by photons from an object or event striking the chip).

We aren't worried.

Edit: first observation of one in like 3 years btw. They are rare.

Edit2: light year is a term that means exactly what you think it means. How far light travels in 1 year. Things are many thousands to millions to billions of LY away.

[Boyiee]

Wouldn't it be a cool way to go though? Fuck asteroids.

[BerenTebogo]

Wouldn't it be a cool way to go though? Fuck asteroids.

Would need to come from one within our own galaxy in and be pointed in exactly the right way. Would be p cool but nuclear winter is the bees knees too.

[Boyiee]

What if we got hit by a big enough rock to end life but on the exact other side of the planet on land and not water. Would we be able to tweet it before we were wiped out like with earthquakes? Lol

[Cail]

Would need to come from one within our own galaxy in and be pointed in exactly the right way. Would be p cool but nuclear winter is the bees knees too.

4 more months!

[Boyiee]

I mean bigger than just block out the sun of course I mean a fucking boulder like mass effect shit

[BerenTebogo]

What if we got hit by a big enough rock to end life but on the exact other side of the planet on land and not water. Would we be able to tweet it before we were wiped out like with earthquakes? Lol

Yes. Absolutely. Shocks would move through the earth at somewhere around sound speed.

[Boyiee]

Fuck yes that's what I want.

[Zetanio]

This thread was built for Sath to shit on people.

Best idea in months.

[Byrthnoth]

It's difficult to predict how far away brain implant prosthetics are because there are a lot of technological hurdles to jump, some of which currently look insurmountable:
1) Onboarding process - Current brain implant prosthetics correlate an action you intend to do with a movement. So there is a long training period where the researcher says "imagine moving your arm in this way" and they have you do it a dozen times and record what your brain activity looks like. Then the next movement, then the next, then maybe combinations, etc. It's an arduous process to say the least to map brain activity to intent.
2) Implant stability - ...and occasionally either your brain signature of intent or the implant itself will change and you have to remap it.
3) Movement precision - Where/what you're moving
4) Brain implant technical issues - infection prevention, implant form factor, number of channels/design, wireless?, etc.
5) Force control - How much pressure your fake muscles put out
6) Tactile feedback - What the prosthetic feels.

People are making incremental progress on 1-4 and they might eventually hit the point where brain implants are worthwhile for people who don't have tetrapelgia. Perhaps that point will be in 20 years (after FDA approval and such).

The big problems are #5 and #6. No one has good solution to and, it turns out, those two problems are pretty important to solve if you want to really use a fake hand. Without #5, you have to automate all force control in the arm and the user won't necessarily be able to control it. Without #6, everything is based on visual feedback. I just graduated from a university at the forefront of brain implant development, went to a lot of talks on this because it interested me, and I can say with confidence that we are a long, long, long, long, longlonglong way from solving either of these problems. #5 may fall out as #1-4 improve, but without tactile feedback there's no way for the user to do force control on unknown objects. I have seen the foremost lab present their research on tactile feedback, and I say to you with confidence that I don't expect to see it working in my lifetime.