Interstellar travel: is there any plausible way that it could work?

Question

We got lots of amazing things from science and engineering, but every one of them conforms to the various physical laws that we formulated along the way. To me that means it's not possible for interstellar travel to be achieved in any useful way.

OK prove me wrong - give me a scheme that works. But to make it worthwhile:

1. the travellers have to arrive alive, and they have to remember why they came. If nipping through wormholes squashes you into putty, no deal.

2. the travellers who arrive have to be the same ones who set out, not some parallel or entangled identical copy, and not the Nth generation descendents who have all evolved back into pondslime.

3. putting them to sleep for a buzillion years is cheating. Moderate snoozes are lame but acceptable.

4. no breaking the laws of physics, unless you have a good reason why you're so much cleverer than anyone else.

5. But you can invent anything you like as long as is theoretically possible

Ah, some great thinkers have attended to this one. Many thanks. To the vote it goes, and please VOTE PROPERLY - the first post isn't always the best (wild eep's law of answers)

Answer 1

It is theoretically possible for a spacecraft to fly to the nearest star in 30 seconds. However, it is an engineering impossibility. People get confused about things. The nearest star is 4.5 lightyears away, but light actually travels that distance instantaneously. We perceive that it takes light 4.5 years to get there, but that's just our perspective. If you were "riding a photon" you would travel the distance instantaneously. (This isn't my speculation, this is 100 year old accepted science, namely the special relativity of Einstein. It has been verified experimentally an incalcuable amount of times).


So speed of light travel is out of the question, but the key is still going fast. Most people think that going fast is somehow dangerous or harmful to humans, but this is incorrect. Acceleration can be harmful if it is too fast, but velocity is unnoticible.

For example, right now we're all traveling close to 70,000 miles per hour around the sun and yawning about it.

Here's the basics: we need engines that can provide thrust for very long time intervals and thus provide low accelerations, as opposed to chemical rockets, which provide great force over short intervals and hence large accelerations.

I won't go into the math, but basically if you were on a skateboard and you always had a constant push on you, say like a good breeze, but if that force were constant, and was always applied continuously, by the time a month had past you would be going ridiculous speeds - like hundreds of thousands of miles per hour.
(clearly the analogy is kind of stupid but I'm just trying to make the point that if a satallite could produce a small continuous thrust it could reach relativistic speeds.)

So these things are in development on a large scale and have already been used on a smaller scale (nuclear engines and ion rockets). Caltech launched one a while back to study a meteor. I forget just how fast it eventually got going, but I remember that the engine was on for around 2 years, continuously. (although the amount of force applied by the engine was much tinier than the analogy above). Remember chemical rockets generally fire for a matter of minutes.


Again: as you appraoch the speed of light, funny things happen to distance and time. So if you could really get close to the speed of light, then the trip could basically take as short as you wanted it to. However the technology for these types of speeds is not on the horizon. Interestingly, although the trip would take a short time for the crew, it would take a long time for the observers, so the crew and observers would become out of sync with respect to time. By the time they got back, basically large amounts of time would have passed on Earth, whereas they would have experienced small amounts of time. This is one of the inconveniences of space travel.


Pretty much all of the scientific community agrees that all engineering problems related to space travel will be conquered. It's just a matter of time, public interest, and yes money.

Let me add a few more things. First, if you're really interested read On the Exploration of Space by Arthur C. Clarke. He was the English physicist who dreamed up the communications satillite, was president of England's equivalent to NASA, and co-wrote the screen play for 2001: A Space Odyssey. The book is for laymen and written extremely well.

Also, let me add that interstellar travel is mostly an engineering problem, not a theoretical one. The theory is there. (excluding research about new sources of energy, which would make the whole endeavor incredibly easy).

Lastly, space travel is not that hard, it's just a question of public interest and resources. Consider how everyone thought that flight was a ludicrous idea, until the Wright Brothers, a couple of bicycle mechanics, built the first airplane. Fifty years later we landed on the moon.

The reason that space travel hasn't developed so quickly is that the benefit is not as immediately obvious as commercial flight, and it's more expensive. But it's very feasable and I honestly find it dissapointing that the general public still thinks that it's a fantastic idea. We should all recognize that it's only a matter of time and hard work.

Answer 2

Well, according to Einstein if you travel faster than the speed of light you would be back to past. Take a shotgun as an example: if you shot a gun an run faster than the bullet, the future (bullet) can never catch you, so you have to return and go back to reach it. That's just a theory.

Anyway, there's another theory in astronomy that says universe is like a tube and you can fold it. So, imagine a point in a corner of a sheet of the paper and another point in the very opposite corner. You can join these points by simply folding the paper and putting one point over the other. This way two far points are together in a blink of an eye. Got it? But i think it's gonna take a long time till we get those technology. Light speed as i wrote before is out of question.

Well, that's a lot of theory i know but not "non-sense".

Answer 3

Currently, there is no imaginable device or method for intersteller travel that could done under your five conditions.

1. Wormholes require non-existant faster than light travel to use.

2. A "Space Ark" is the most plausible way to transport people between solar systems, but this would take many generations and thousands of years.

3. Even if we could put people in a state of suspended hybernation for extreme periods, this condition would exclude it.

4. Same as number 3, even if we could break the laws of physics, this number excludes it. Although the law that does not break must surely bend *cough* Tachyons *cough*

5. Isn't ANYTHING "theoretically" possible? Heck, ok I got one. I'll invent a "super donkey" that looks exactly like a regular donkey except instead of blood, it has a type of organic rocket-fuel blood that allows it to travel faster than light. People just get on the donkey and it flies them to wherever they want. See, its theoretically possible.....but way stupid.

Answer 4

It may not even be possible to travel long distances within the solar system, as the EM spectrum exposures may be physically and mentally toxic.

Shielding from these spectra would place the inhabitants of the craft at risk for bombardment from molecular pieces of the panelling, as the craft was hit by the radiation.

So, we need to solve this problem first.

Answer 5

Very good question. Most crucially it would be necessary to invent a vehicle that can travel near to the speed of light (notice I say near to not faster so as not to break rule 4!) This makes the whole journey across space easier. Coupled with this it would be necessary to invent a device to be installed on the vehicle which would preserve a stable environment for the passengers i.e they aren't mashed into atoms when accelerated to a near light speed velocity.

Answer 6

Okay first of all, we would need to travel at the speed of light. Here is my theory disproving why light speed travel is impossible.

Theoretically, traveling at light speed would be impossible. As I stated in an earlier post: Since it is projected that nothing can travel faster than the speed of light, you would need a force greater than light to travel at the speed of light. I even worked out an explanation of why it wouldn't work in my theory, I'll look for the paper and type it down. I wrote this in math class.

Theoretically, for an object to travel at the speed of light, it must have the same or lesser mass than light. for example, say a space shuttle weighs 100 tons. it's propellant is expelled at the speed of light, and it's force is x. the force remaining after moving the space shuttle is x-100 tons, and since it is thought to be impossible to travel faster than light, the space shuttle's propellant cannot travel faster than light.
(I left out the last part, because it was disproven by deeper thought.)

(C) Copyright 2006 by Paul Burke. Punishable by law, this writing can not be reproduced without the sole permission of it's main distributor.

In short, it's the first nail in the coffin.

I'm actually siding with you. It is impossible.

Next, we would need enough supplies and the strongest type of like "armor" for the vehicle to handle the extremes of outer space. Even something like this would be very hard to get out of the atmosphere, given the extreme weight. Supplies would only add more weight and room. Another nail in the coffin.

We have already succesfully traveled into space with hundreds of launches, I think that insulation will not be a problem.

IF in fact we COULD travel at the speed of light, making me stupid, it still takes billions of years to travel to and from large interstellar bodies. Same travelers that set out still alive, impossible unless you had a male and female, if you catch my drift, but they would need a son and daughter, and eventually reproducing through the same bloodlines would make them dumber than sawdust, yet another nail in the coffin, unless you had more than one family at a time, still the bloodlines would catch up and screw with the kids, extending the nail in the coffin.

Medical science has not advanced far enough to effectively and professionaly cryogenically freeze someone to make the travel, and what if something goes to hell on the travel like a comet impacting the vehicle while our little astronauts are snoozing away in a bath of cryogenic bliss. The next nail in the coffin.

Oops, never talked about your first rule. I'll do that, but I think that was already tackled. There is no evidence of wormholes anyway, another nail in "Le coffin".

Thanks for the generosity of your 5th rule, but being theoretically possible, that would take another eternity to develop the technology required. I know you're getting sick of this but,

ANOTHER NAIL IN THE COFFIN.

And breaking the laws of physics even with a good reason, it's impossible. You may be able to break earthly rules like "No jumping on the bed" but momma physics is much more strict than good 'ol mom. Another nail in the coffin, you cannot break the laws of physics. Unless you were able to theoretically alter existence as we know it, but mother physics wouldn't like that too much and just collapse the whole universe. So that just extends the nail in the coffin, probing the half-living heart of this theory of interstellar travel.

Another idea that is impossible, teleportation, relating to wormholes. This also relates to taking a buzillion years for the correct tech to be developed. Making use of teleportation, in theory, would have to somehow incorporate an unbreakable law of physics, and again mother physics is not leniant at all. "Hey look! Is that a guard and an impenetrable electric fence to watch for graverobbers?".

I leave you with this statement: very well thought out, analytical question leaving me some space to help disprove interstellar travel and be as creative as I want. Thanks, this was fun. I like answering questions that are this analytical with some solid ground rules too. Sorry for such a long-winded answer.

Answer 7

Maybe as you enter a wormhole our body's may start to change maybe vibrate at a higher frequency than we do on this plane then we may loose our physical body and temporary go to our energy form and then we could pass through quite easily.

Answer 8

Look at it this way we went to the moon in the 60's. Now we can only just about reach mars. Is that enough of a reality check

Answer 9

Some long answers here, how about this short one.

1. Bussard Ramjet to get you out of the Solar System.
2. Black hole to get you where you want to go.
3. White hole to get you back again.

easy?

Answer 10

Interstellar travel... hmm travel between stars... got it.

Begin life as a virus, infect Brad Pitt, when he kisses Angelina Jolie transfer to her. Presto, travel between stars, mission accomplished.