141–150 of 500 posts
What does it mean that I’m “looking at the big bang”?
This is something I've wanted to try in VR one day. Does anyone know if there is an app/game available for one of the popular headsets? Is there a technical limit to how realistic the effect could be?
> Is there a technical limit to how realistic the effect could be? You won’t feel the acceleration ;) nor the light intensity of the higher velocities (luckily).
Years are passing in seconds in this websites simulation, if you were experiencing it all in "real time" everything would appear pretty much stationary for quite a while.
Even at like 95% the speed of light, you're talking about years of time required to move between stars - nothing will appear to change much day to day until you actually get close to one of them.
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dumb question - why does going faster make it more likely you encounter fast protons? couldn’t protons in any reference frame be going quite fast relative to you?
not so much protons (which would be a problem, but could at least notionally be deflected), but atoms.
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That's silly. My flashlight shoots stuff at speed of light all the time. Mass matters. Shooting just enough mass at very high velocity is not much different than shooting a lot more mass at lower velocity, in terms of force.
> Mass matters. Exactly. You try accelerating 200kg up to anywhere close to the speed of light (say 80%). That is a lot of force. Technically even photons can exert force on objects, but they have such a small mass that it's a difficult effect to observe.
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Not exactly what youre looking for, but this type of game (using relavistic physics) has been attempted. Heres one built in unity that could be easily ported to a Quest line device. https://en.m.wikipedia.org/wiki/A_Slower_Speed_of_Light I also found this render (and game!) that show off some aspects of relativistic spaceflight. https://youtu.be/Ix1XlxF66Zk?si=8HzDH3U-CRM-erRB I think the technical limit might be moo…
Thats great! I wonder if the stomach issues would be eased if you were sat in a chair like captain kirk looking through a big panoramic window.
Yikes. At around 90%c, it's starting to look like a sunny day. Any physicists care to weigh in on the accuracy of this? I can search for the energy density of starlight in interstellar space... but how fast does one need to go to hit that "sunny day" point?
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I suppose you would also have to worry about surviving the trip - every atom in the interstellar medium would damage your ship, likely penetrating the entire way through, and electromagnetic repulsion would only work with charged particles.
Every proton would have the energy of a baseball. It's bananas. Granted, space is really empty, but it's not that empty, somewhere around a hundred atoms per cubic meter. Your ship might look like a very, very long shooting star. Probably dialing the speed down a touch would be worth it for whatever your shielding material is, but who knows? We're talking miracle engines here. I think in the "Valkyrie" ship-on-a-stri…
I’d never seen “a hundred atoms per cubic meter”, but it’s always been my intuition that, without some quite interesting shielding, you couldn’t make it anywhere near the speed of light. And on the other hand, I’ve seen claims that “space is really big” as you mentioned; but that claim has always seemed dubious.
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> Could any somewhat-plausible technologies (fusion etc) get us to that point? Nuclear thermal or nuclear pulse propulsion. No fusion needed.
For practical values, nuclear pulse propulsion would only get you up to a few percent of the speed of light. The best nuclear thermal, gas core, would give you 7000 seconds[0]. A "dusty plasma" rocket (suspend the nuclear fuel in dust form in a magnetic field) might get 100,000 seconds, or just over a day of accelerating at 1g. [0] for the benefit of non-space nerds: the unit of measure is "lb-force seconds per lb-ma…
I think you mean “a very large fraction of the total mass”… generally the best efficiency comes if your fuel mass fraction is high, as it means there is little overhead of things in your spacecraft of things that are not fuel (the mass of the engine, etc)
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Unless you could somehow make an Alcubierre warp drive. Of course…even if that was possible, it’s conjectured that the colonists already at your destination won’t appreciate you boiling the atmosphere when you hit them with blue shifted radiation. https://www.universetoday.com/93882/warp-drives-may-come-wit...
> it’s conjectured that the colonists already at your destination won’t appreciate you boiling the atmosphere when you hit them with blue shifted radiation. There's a general principle known as Jon's Law (not sure where the name comes from) that any powerful space drive is by definition a weapon of mass destruction. You see this in The Expanse when incredibly powerful fusion torchship rockets (a major part of the Exp…