The difficulties of interstellar travel and the implausibility of the Extraterrestrial Hypothesis.

reply to post by Diablos

The paper you quote is fairly well-known in certain circles.

All this stuff about traveling around the universe in space suits – except for local exploration, which I have not discussed – belongs back where it came from, on the cereal box.

That statement so incensed Arthur C. Clarke that he spent a good part of the rest of his life thinking of ways to refute it. It also provoked him into formulating what he modestly termed Clarke's First Law:

When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.

It saddens me to think interstellar travel may be forever barred to us, but I am consoled by the thought that the same barrier should then exist for others. I am not one who believes that scientific advance and technological accomplishment automatically go with high ethical principles and love for one's fellow-sentients. They certainly have not always done so on Earth.

A star and a flag for you, and a bump for my own thread on the same theme (though with different subject-matter), Near-Light-Speed Starships May Not Fly.

As is detailed in the OP, interstellar travel in C Space (Relativistic) is described as near insurmountable knowing what we know about how the universe works.

It's also alluded to that another methodology would likely be employed as agency for "FTL" in side-stepping the whole C-Space problem.

It may have been mentioned, but, we are currently working on feasability studies for proof of concept regarding the Alcubierre Drive proposal. New calculations suggest the energy requirement to achieve the proposal are far less costly than initially posited.

NASA engineer/scientist Harold Sonny White brought this concept back tot he table and is spearheading the efforts into confirming feasability and proof of concept.

There are, of course, other more Science-Fiction methods that often come up as explanation, like wormhole travel, but, as fun as such concepts are in the movies, and paperback, we've no current working theory for propagation, sustaining and/or even targeting a traversible Wormhole, so, we can't realistically propose such a thing is even possible from an engineering standpoint regardless theoretical models describing these geometries.

While I don't support the ETH as having any degree of probability, I don't deny the possibility that we ourselves may achieve in the Alcubierre Drive, thus also confirming possibility for any imagined alien species with sufficient technological sophistication to develop the same.

Note; there is a difference between possibility and probability.
Note also; regardless possibility and even probability, such does not at all guarantee the existence of any sufficiently technologically sophisticated alien civilization capable of facilitating the above, much less paying us any visits.

EDIT: after this posting, OP was updated to include Warp Drive.

In the 1960’s what we’re all doing right now would have seem utterly impossible. If you were to explain the modern day internet to an average man or woman from 1963 they’d think you were talking complete nonsense. So many things - LED TV’s, bluetooth devices, wifi, even touch screen items would have seemed very alien to them fifty years ago. In 1963 these guys probably thought it impossible to land on the moon...

I, for one, believe we have been and are being visited. For what reason, who knows? As for how they get here, we cannot even begin to explain how they’d do it. They wouldn’t use something as relatively primitive as rockets.

Here's a little quote related to quantum gravity, from the Web site of Vienna University of Technology:

The cosmological constant problem entails a gigantic discrepancy (123 orders of magnitude) between observation and naive theoretical expectation, and so far no satisfying explanation exists that resolves this discrepancy.

itp.tuwien.ac.at...

Until we have a valid theory of quantum gravity worked out, it's premature to claim that it's impossible to propel spacecraft at superluminal speeds. Einstein talked about "dynamic aether," yet mainstream physicists ignore it.

It goes the notion of zero-point energy and zero-point propulsion, which if possible, could account for the seemingly impossible flight characteristics reported by a lot of pilots and other witnesses.

Originally posted by xpoq47
Until we have a valid theory of quantum gravity worked out, it's premature to claim that it's impossible to propel spacecraft at superluminal speeds. Einstein talked about "dynamic aether," yet mainstream physicists ignore it.

While it is true that there are still problems not adequately explained, such as quantum gravity, this does not mean it will give us any major practical applications. Why? A comprehensive theory of quantum gravity must reduce to general relativity in the macroscopic case, and general relativity effectively rules out anti-gravity. So, it might be a scientific interest even if anti-gravity effects can be generated on 10^-27 scale, but it doesn't look like we'll ever have any macroscopic instances of such a phenomena that can be engineered.

Originally posted by xpoq47It goes the notion of zero-point energy and zero-point propulsion, which if possible, could account for the seemingly impossible flight characteristics reported by a lot of pilots and other witnesses.

Except it is impossible. If it wasn't, then that would violate one of the most fundamental cornerstones of quantum theory. The zero-point energy field is a result of the fact you cannot take out all of the energy of a vibration, otherwise atoms would be stationary at their equilibrium position and you could deduce both their position and velocity simultaneously which violates the uncertainty principle.

reply to post by BlindBastards

1960’s what we’re all doing right now would have seem utterly impossible.

I think you are wrong there, in the 60's the future existed and was bright, today there is no future beyond bare survival and planing for the next political circus...

reply to post by Diablos


It's a bit of a radical approach, perhaps, but what if gravity is the result of radiation pressure of ubiquitous weak photons that hold matter together just as air pressure holds a ball of water together suspended in midair in an orbiting spacecraft? It means those photons are hitting every particle of matter from all directions but are ever so slightly rarified in the directions over the horizon if you're standing on the surface of the Earth but extremely rarified if near the event horizon of a black hole. The Earth is a weak shield against particles from directions over the horizon, slightly upsetting the balance of radiation pressure from all directions, resulting in what we call 1-g gravity. But a black hole demonstrates just how powerful that bombardment is by blocking a high percentage of it from one direction.

That's radically different from the way people normally think of gravity, but it also means that special relativity is a result of something like wind resistance as you're trying to plow through that onslaught of almost infinitely weak but almost infinitely numerous photons.

If that's not how gravity works, then how do gravitons pass through the dense core of the Earth unabated and grab things and pull them back, not to mention travel in the wrong direction from a black hole to reach out and grab things? If you say it's warped space, then what is space made of? If nothing, there's nothing to warp but the one free proton per cubic centimeter verified by radioastromy to exist in space plus the molecular hydrogen that goes undetected and the more rarified oxygen and other gases in space--so basically no Jello to warp.

And zero-point energy can be thought of as just a quirk of the theory of quantum mechanics, but inability to freeze helium and the Casimir force are two indications that there is something there. But one more is the "mystery" of how electrons maintain orbit. Orbits decay, but electrons somehow get a little boost from something that's right there for the taking. The tail of a comet is similar but can be explained mostly by its bucking the solar wind, but even that shows that light pressure is real, not just something mentioned in the context of solar sails. Some experiments with SQUIDs (superconducting quantum interference devices) also show that there is something there.

Einstein mentioned this but was pretty much ignored. it doesn't violate Special or General Relativity but shows a reason for them rather than just models that only describe their consequences.

But it does leave open the possibility that UFOs can do exactly what the late astronaut Deke Slayton, former USAF Chief Public Relations Officer Colonel William T. Coleman, and many other pilots, police officers, Skyhook balloon trackers (once together with an astronomer) and others have said they clearly witnessed.

And astronomers like to say that the galaxies beyond the Hubble horizon are moving away from us faster than the speed of light, although the existence of molecular hydrogen in space would seem a better explanation to me. It was shown to exist and written up in Nature in the late '90s but somehow remains pretty much ignored.

reply to post by Diablos


Cool. Now let's apply things that have yet to be discovered as a way of travel. So it is impossible and always be impossible? There is always a way, that's rather close mindness to think no way will be developed, not until all that has to be discovered is discovered.

I don't know what might be discovered one day, teleportation, hyperspace, I've no idea. If one type of technology reaches its limits and cannot be made FTL, another one may be discovered, you never know..

The galaxy motion thing: superluminal motion. The Cliff Notes version is it could all be an optical illusion, but isolating that as a hard fact will have to wait until we get multiple viewing angles.


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Did i just read "The absurdity of faster than light travel" ? In terms of physics and what we know about them we are stil at the begining, because we know a limit today, doesn't mean that limit will be there tomorrow, because someone from almost 100 years ago said light speed is the limit, doesn't mean that is the limit. Just look at how many old theories have been changed or proven wrong.

Its just like the idea that aliens need water to function even though we have such a small grasp of biology.

This ignorance of so called "scientists" amazes me. They are so narrow-minded it makes you doubt their intelligence.

I think it would have to all be based around the molecular level and de-materialization.

Cutting right through space rather then taking the long way.

There is one method I can't seem to get out of my head. Magnets/Electricity

Problem is getting them to speed up fast enough to power massive generators that could power nuclear fusion reactors which could power ____ etc... Self-sustaining for an endless journey.

But there's probably a really simple answer like using water or hydrogen somehow

reply to post by yourmaker


I repeat, we don't know everything, there might be other ways and other limits, 1 000 000 times the speed of light maybe?

Energy sources like shrinking down neutron stars and using them?

great post OP, reminded me of this excelent place which discuss STL and FTL interstellar travel

www.projectrho.com...

www.projectrho.com...

So you give someone an inch and they want a yard. Given them a rocket ship and suddenly they want a star ship. SF writers want to use exotic settings on alien planets, but the real estate in our solar system mostly looks like a bunch of rocks. I know that those spoil-sports at NASA have ruined our solar system for SF writers since their nosy space probes failed to find dinosaur-infested jungles of Venus and scantily-clad Martian princesses. But they haven't sent probes to other stars yet! Why not turn my rocket ship into a star ship?"

Unfortunately it isn't that easy. The basic problem is that interstellar distances are freaking huge.

Consider: a single light-year is an inconceivable abyss. Denumerable but inconceivable. At an ordinary speed -- say, a reasonable pace for a car in a megalopolitan traffic, two kilometers per minute -- you would consume almost nine million years in crossing it. And in Sol's neighborhood, the stars averaged some nine light-years apart. Beta Virginis was thirty-two distant.

Let's make a mental model. Say the scale is such that one astronomical unit is equal to one millimeter (1/25th inch). There is a glowing dot for the Sun, and one millimeter away is a microscopic speck representing the Earth. The edge of the solar system is about at Pluto's orbit, which varies from 30 mm to 50 mm from the Sun (about 1 and 3/16 inch to almost 2 inches). Imagine this ten-centimeter model floating above your palm.

This would put Proxima Centauri, the closest star to the Sun, at about 272 meters away. That's 892 feet, the length of about two and a half football fields or four and a half New York city blocks! Glance at the ten-centimeter solar system in your hand, then contemplate the nearest solar system four and a half city blocks away.

And the center of the galaxy would be about 1600 kilometers away (about 990 miles), which is a bit more than the distance from Chicago, Illinois to Houston, Texas.

while Faster-Than-Light travel is about as handwavium as you can get, it is unfortunately the sine qua non of interstellar space opera. Space opera with no StarDrive is like chocolate cake without the chocolate. FTL is sometimes called "superluminal". In vintage SF, the propulsion was commonly termed "hyperdrive", since the starships evaded Einstein by entering a dimension called "hyperspace" where there was a higher speed limit.

Star Trek has its "warp drive" that reduces the distance to be traveled by warping space. The RPG Traveller has its "jump" drive that teleports the ship from point A to point B. In his "Lucky Starr" novels, Isaac Asimov uses the term "Hyperatomic spaceships", presumably since the spacecraft had both a faster-than-light Hyperspace engine and a more conventional atomic engine

Originally posted by AlexIR
Did i just read "The absurdity of faster than light travel" ? In terms of physics and what we know about them we are stil at the begining, because we know a limit today, doesn't mean that limit will be there tomorrow, because someone from almost 100 years ago said light speed is the limit, doesn't mean that is the limit. Just look at how many old theories have been changed or proven wrong.

Its just like the idea that aliens need water to function even though we have such a small grasp of biology.

This ignorance of so called "scientists" amazes me. They are so narrow-minded it makes you doubt their intelligence.

Actually, it means exactly that. The laws of physics do not change as a function of time, otherwise they wouldn't be considered laws in the first place.

Just exactly how many theories were "proven wrong"? Sure, there were many theories that needed to be modified to be included in a more general frame, but that does not mean they were outright wrong. We know Newtonian gravity is now an approximation and is "incorrect", for example, but that does not mean that the force gravitational force between two masses predicted by Newtonian gravity is now wrong. Similarly, if a new framework supersedes special relativity, it will have to reduce to special relativity at speeds close to the speed of light and agree with the prediction that nothing can travel faster than light.

Just because there are things we do not understand at the moment is no excuse to invoke fantasies that we know are impossible. Finding a phenomena that cannot be explained via special relativity does not mean we will magically begin to see particles whizzing at speeds faster than the speed of light.

Also, funny how we're no closer to "breaking" the speed-of-light limit today than we are 100 years ago.Kind of invalidates the endless technological extrapolations, don't you think? After all, 100 years ago, who could have imagined the internet or nuclear power? That obviously means we'll have warp drives and perpetual motion machines soon, doesn't it?

Even if we achieved to reach the speed of light or faster, no one could survive it. The only way to space travel to other galaxies would to be teleported through a wormhole or something. High chance of not surviving that either.

reply to post by Diablos

If we apply current thinking to the problem then clearly we can never accelerate to light speed let alone the impossibility of going beyond. The 60's thinking is based on rockets ! I mean come on.

Let's throw in a wobbly here shall we: gravity. As yet it is still not understood. It is believed there is a graviton to "fit" gravity into the standard model. That assumes the standard model is the be all and end all of particle physics. It might not be. Since gravity is not yet understood there is a distinct possibility that all current thinking is locked into the inward looking limitiations of Einstein. Relativity is linked to mass. It is the change in relative mass that prevents the rocket from accelerating to light speed and it is that pesky mass that is linked to gravity and the curvature of space. Soooo

Let's grab the higgs boson. Tear it apart, find out how it ticks. Determine how it imparts mass and apply an anti-higgs field. hey presto matter is massless (or de-coupled from the rest of the universe) and no light limitations apply.......

Clealry I am being very simplistic BUT you cannot argue that our lack of knowledge about gravity, inertia and the higgs field opens the way for a possibility of FLT travel?

Star Trek has their warp field , we will have the higgs bubble.

Want to let the imagination rip ? Any budding sci fi novelists out there? Since a higgs bubble de-couples the interaction between the enveloped matter and the rest of the universe whatever is inside the bubble is invisible. There is no change in rest mass inside the bubble, no inertia and therefore infinite acceleration is possible. The problem is navigation !!!!!!!!!!!!!!!!!! Highly accurate maps, timers and computers will be needed as you "fly" blind. Don't want to switch the higgs bubble off inside a star ! (maybe George Lucas was onto something )

FYI : I am not yet convinced of ET's visiting earth but I am open to the possibility whilst the book of physics still has blank pages.

100 years ago, if you told someone we'd have men walking on the moon, they would have believed it to be just as ridiculous as you (OP) believe it to be for interstellar travel. If you had told me when I was a kid, that I'd have a phone in my pocket, where I could call anyone in the world, take pictures, navigate me to a location, and access nearly all info I'd ever want to know....I would have thought you insane.

Is it really that unbelievable? To me, the cell phone would have seemed MORE unlikely, than us (or an older, alien race) figuring out how to traverse the vast distances of space.

reply to post by Diablos


You present a somewhat arrogant and short sighted viewpoint. The human race, at this time, is not the font of all knowledge, therefore we look at the problem of interstellar/FTL travel through primitive eyes. We honestly have no clue of what is or isn't possible and what rules can or cannot be broken. To shrug your shoulders and suggest that we know all there ever is to know is kind of ridiculous. We can say nothing with any degree of certainty.

IRM

Very interesting. It doesn't matter who looks at this or how smart that person is, their perspective will always be formulated from within the paradigm of physics as we currently know it. We can say that the rules of physics remain constant throughout the universe, but we really don't know that to be true... we only assume that it is. Perhaps there are different elements found on other planets and in other galaxies that we are unaware of and these elements change the possibilities in that place, but we are unaware of that. Lately there has been a lot of talk about how we exist within a computer simulation. If that is true, then all of the rules that apply to us are written in some type of code, advanced code, but code nonetheless... and it is only a matter of time before that code is broken. Anyway, great thread and great discussion.