Near-Light-Speed Starships May Not Fly

A blog post on the website of Icarus Interstellar, a foundation 'dedicated to achieving interstellar flight by 2100', suggests that deep-space travel at near-light velocities is probably impossible, and explains why.

A Starship Bathed in Heat, and not a Star Nearby

The reasons given are drag from high-energy photons and heat due to Doppler inflation of the cosmic background temperature.

As a relativistic starship moves through interstellar space, it would encounter photons from numerous sources including the CMB, ionized atomic hydrogen, stars, quasars, the occasional gamma ray burst, etc. During ultra-fast subluminal travel, these radiations would create significant drag on the bow of the starship.

As a starship accelerates toward the speed of light, the normal background temperature of 2.7 Kelvin is Doppler inflated, and a rapidly warming heat bath surrounds the spacecraft... My research supports the contention that at speeds very close to the speed of light, the temperature of this heat bath is high enough to melt all known materials.

Depressing if true. Anyone care to discuss this? And let's try not to derail the thread into discussions about faster-than-light travel, please...

Looking at the heating issue.
Heat is just energy isn't it?

We could probably either convert that heat to something else. Like siphoning it away to convert it into more energy.
Or I bet we could come up with a way to buffer the heat.
Maybe with some electro magnetic field or some other exotic process.

raise the shields !!

aiai captain !!

reply to post by Astyanax


You want an open discussion yet you demand that no one brings up the possibility of faster-than-light travel?
Which incidentally might actually be the solution to the presented heat problem since wormholes remove the whole friction aspect from the dilemma.

Originally posted by laurentius
raise the shields !!

aiai captain !!

That's what I was going to suggest: some sort of "cocoon" (magnetic bubble or whatever) surrounding the ship -- or at least at the bow -- protecting it from the friction.

If we're talking about classical chemically fueled crafts then we're talking about crafts which will never get any where close to the speed of light. Other propulsion mechanisms hold the key. Namely, a warp drive mechanism which doesn't thrust the ship through space, but thrusts space around the ship. This is theoretically possible but scientists say it would require dark energy to power the ship, and we don't yet know how to harvest such energy. Moving space around the ship by warping it would side-step all these problems related to friction and heat (and it would also allow FTL travel since space can warp faster than light).

What if one was able to pass THROUGH the particles, with a magnetic barrier that separates the craft from all other matter outside the barrier?

Is this not how the T3RB is suppose to work? Cloack the craft in a magneticly charged bubble and it wont be subject to external forces, not even gravity...

Once you get that sorted it wont matter whether youre above or below the speed of light.


Posted Via ATS Mobile: m.abovetopsecret.com

What if one was able to pass THROUGH the particles, with a magnetic barrier that separates the craft from all other matter outside the barrier?

Is this not how the T3RB is suppose to work? Cloack the craft in a magneticly charged bubble and it wont be subject to external forces, not even gravity...

Once you get that sorted it wont matter whether youre above or below the speed of light.


Posted Via ATS Mobile: m.abovetopsecret.com

Well if you were to accelerate a ship to near speed of light, I would think it would cause a whole range of problems, such as time passing more slowly/faster(depends on how you are observing), or plowing into the side of a planet or sun. A more plausible why to achieve space travel would be a 'warp drive', which would expand and contract space around the ship, so the space inside the bubble remains constant and space outside is what changes.
NASA is actually working on this theory
techland.time.com...

Um...Deflector shield hello...

Yes, I had read something of the sort a few months ago.
The problem, as I understand it, arises in the process of accelerating an object to near-c velocities.
There is an exponential grow on the "drag forces" (lol, policeman with skirts)
There's also the fact that you can never achieve c, and while I think there is no theoretical limit on speeds > c, the mere concept of space-time and movement at FTL gets messed up...

Perhaps a way to tackle this is, instead of trying "mechanical" solutions (ie shielding), to try to take such interaction out of the ecuation before it gets "critical"
I wouldn't know where to start, and I'm really not qualified to offer alternatives, but I know there's a bunch of super-nerds (real heroes) trying to find a solution to this, which is comforting...

Maybe instead of stopping incoming mass, make it so the "bubble" doesn't even interact with massive particles, if that even means something...

Originally posted by abeverage
Um...Deflector shield hello...

What, exactly, is this deflector shield supposed to be made of? Some kind of manipulated magnetic field? It's still going to be essentially "attached" to the ship, and will accumulate the same amount of drag, or possibly even more because it's going to be so much larger than the ship itself.

My problem with near lightspeed travel is the potential for a virtual particle shockwave pushing ahead of the bow.



The faster you go, to the point where you're compressing spacetime ahead of you as you travel, the more you're going to get an extra load of virtual particles being pushed into reality in the shockwave.

Wormhole travel? Sure. All we'd need is to generate the gravitational force of a black hole in the center of the galaxy, and then a counter-force to keep us from becoming a thin film of information on the surface of that black hole. Piece of cake!

Bottom line is that we'll likely never be able to physically travel any great distance in space, so we'll have to rely on our video games to satisfy that desire while we sent our immortal artificial intelligence machines out to do the real exploring for us. If we still care about it. We'll probably eventually lose interest in the whole idea.

Originally posted by Blue Shift

Originally posted by abeverage
Um...Deflector shield hello...

What, exactly, is this deflector shield supposed to be made of? Some kind of manipulated magnetic field? It's still going to be essentially "attached" to the ship, and will accumulate the same amount of drag, or possibly even more because it's going to be so much larger than the ship itself.

My problem with near lightspeed travel is the potential for a virtual particle shockwave pushing ahead of the bow.

The faster you go, to the point where you're compressing spacetime ahead of you as you travel, the more you're going to get an extra load of virtual particles being pushed into reality in the shockwave.

Wormhole travel? Sure. All we'd need is to generate the gravitational force of a black hole in the center of the galaxy, and then a counter-force to keep us from becoming a thin film of information on the surface of that black hole. Piece of cake!

Bottom line is that we'll likely never be able to physically travel any great distance in space, so we'll have to rely on our video games to satisfy that desire while we sent our immortal artificial intelligence machines out to do the real exploring for us. If we still care about it. We'll probably eventually lose interest in the whole idea.

Fine fold space...no drag.

Never say never...

Originally posted by drakus
Perhaps a way to tackle this is, instead of trying "mechanical" solutions (ie shielding), to try to take such interaction out of the ecuation before it gets "critical"
I wouldn't know where to start, and I'm really not qualified to offer alternatives, but I know there's a bunch of super-nerds (real heroes) trying to find a solution to this, which is comforting...

The only potential solution to this problem is a work-around that involves somehow amplifying "consciousness" so that we can psychically travel to where we want to go, and not rely on physical reality. The Army's remote viewing experiments determined that there is such a thing -- extremely weak and unpredictable -- and it is not locked into ordinary spacetime as we know it. Past, present, future, anywhere in the universe. You can let yourself go there. But right now there is no good theoretical basis for it. It can apparently interact with EM fields, but it is not inherently electromagnetic, so we don't know how to manipulate it or even adequately measure it. It's more in a different dimension of understanding than physical reality.

But, someday we may be able to get a handle on it, and then we'll be able to hook up to a ship or a super-evolved X-Box and experience travel and create a presence anywhere and anywhen in the universe. Then we will be the time and space traveling UFO pilots. The "aliens."

Originally posted by abeverage
Fine fold space...no drag.
Never say never...

Why would folded space not have drag? Seems to me that folded, higher-density space would have even more drag.

And the only way we know of to fold space is with gravity created by mass. How do you create enough gravity to fold space without folding yourself into it, also? Implode two galaxies? Even if we could manipulate things on that scale, it would still take millions of years for even the implosions to happen. Humanity has only been around for 40,000 years. We'll be long dead and gone.

Originally posted by ChaoticOrder
If we're talking about classical chemically fueled crafts then we're talking about crafts which will never get any where close to the speed of light. Other propulsion mechanisms hold the key. Namely, a warp drive mechanism which doesn't thrust the ship through space, but thrusts space around the ship. This is theoretically possible but scientists say it would require dark energy to power the ship, and we don't yet know how to harvest such energy. Moving space around the ship by warping it would side-step all these problems related to friction and heat (and it would also allow FTL travel since space can warp faster than light).

edit on 21/2/2013 by ChaoticOrder because: (no reason given)

Isn't this basically the theory of bending space, moving a ship at regular speed into the new space and then unbending it with the result being the ship has moved faster than its regular speed?

Apparently, If I understand this theory, your only limited to how much space can be bent by your power source. Theorhetically you could fly from here to mars in a matter of a few seconds if you had the power to bend the space between the earth and the red planet.

Originally posted by Kody27
Which incidentally might actually be the solution to the presented heat problem since wormholes remove the whole friction aspect from the dilemma.

Who says there is no friction in a wormhole? Seems to me that the event horizon of a wormhole would pretty much be infinite friction. A sphere of solid space that a real particle couldn't even get through. Unless you're going to somehow magically switch all your real particles to virtual to jump the barrier. Good luck with that.

Originally posted by Hopechest
Apparently, If I understand this theory, your only limited to how much space can be bent by your power source. Theorhetically you could fly from here to mars in a matter of a few seconds if you had the power to bend the space between the earth and the red planet.

Even if you had the (literally) massive power do it, I don't think that pulling Mars in so that it's within stepping distance of Earth is the best idea.

Originally posted by Blue Shift

Originally posted by abeverage
Fine fold space...no drag.
Never say never...

Why would folded space not have drag? Seems to me that folded, higher-density space would have even more drag.

And the only way we know of to fold space is with gravity created by mass. How do you create enough gravity to fold space without folding yourself into it, also? Implode two galaxies? Even if we could manipulate things on that scale, it would still take millions of years for even the implosions to happen. Humanity has only been around for 40,000 years. We'll be long dead and gone.

You are making Baby James T. Kirk cry...

Interstellar 'starships' are a great concept to act as incentives for scientific ambition. Sure, the concept might be a little simplistic right now, but it's only by exploring the obstacles that we'll have any chance of finding a way around them.

Even getting out of our own solar system will be a massive task and won't be accomplished by just avoiding the planets. There are so many dark masses in the voids that hurtling to points elsewhere at full-throttle would potentially be a short-lived adventure creating a light show visible from Earth. We tend to think of space as a vacuum in the sense of being devoid of anything whereas it's littered with untold numbers and unknown masses of high-speed objects. Dust is bad enough.

The Voyagers have snuck out to the outer limbs of our system so it's possible to mooch a small craft some of the way. However, I'm not sure we even know the odds of repeating that success. It isn't even clear what lies beyond what we currently define as the heliosphere.

On that point, interstellar travel might have to embark from points on the edges of the solar system. It's quite depressing really. Here we are looking ahead to future missions to Mars and it puts it into perspective how many life-times it could take to put a human foot on a moon or planet further away.

Damn. Our ambitions suddenly seem like a lonely cry in the darkness and nobody's listening....sigh...