# What if one could travel at a speed where one could reach nearest star in 13 years, could we handle the G Forces invovled?

I have always been a sci-fi lover. From a young age i regularly watched battle star galactica, star trek, star wars…i just love these kinds of movies and tv series. The idea of space travel all around the universe is stuff of childhood dreams and i simply cannot get enough of the entertainment industry portrayals of travel to new worlds.
I guess one has to learn as one gets older, that just like the fables of Santa Clause and magic, science fiction portrayals of space travel are highly unlikely given the enormous forces involved.

I was reading an interesting article this morning and it presented some data that dampens the star trek idea of warp speed and stopping from such speed in a short period of time and has quite frankly ruined my day.

Apparently, in order to reach the nearest star in even 13 years, one would need to travel at about 100,000km/s.

No problem one might say, one day we will have technology capable of producing the kind of thrust needed in order to achieve that, however, what one may not realize is that the old saying “what goes up must come down” also applies to such incredible speeds in that we must also be able to slow down again and/or maneuver around objects one wishes to not collide with.

In Star Trek movies they seem to be able to stop from Warp speeds in just a few seconds (TV time of course), however, what we are not told is the G-Forces generated by such deceleration…now substituting the warp speed thing for a minute for the speed one would need to travel at in order to reach said destination in 13 years it would take to reach our nearest star at 100,000km/second, and remembering this is a lot slower than it takes the Enterprise to reach its destinations, the amount of force generated in stopping an object in Star Trek time whilst traveling at this speed would be 1 million g!

If one wanted to turn a spacecraft travelling at 100,00km/sec at an acceptible g-force of say 25g, in order to avoid hitting an object in our pathway, one would need to initiate the turn at a distance of 40 billion km’s or about 5.5 times Pluto’s Aphellion (i believe Aphellion is a planets farthest distance from the sun)

A sad day for Star Trek fans

What this does show us, however, is that the idea that God can travel at the speed of thought is truly incomprehensible for the human mind and certainly outside of any mortal humans physical capacity to handle the g forces involved.

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You might enjoy the book The Sparrow. We had a discussion on it on the forum you can probably search for, but your title question was essentially answered in the book by having the vessel accelerate the first half of the journey, then de-accelerate the last half, so was constantly doing one or the other. But you are right about objects in the path. Hitting something the size of a grain of sand at that speed would be disastrous.

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I guess this for me is one of the disappointments in growing up into adulthood…my childhood dreams of space travel Star Trek style have been dashed. Having said that, whilst probably not the greatest lure one may use in spreading the Gospel, the idea that those who are saved and do go to heaven may travel to other worlds is pretty awesome for us Star Trek lovers. (might i also add at this point, i had no idea that Battle Star Galactica was a series produced by the Mormon Church)

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I’ve got a son who would totally nerd out with you over all this - and I’ll be happy to ‘nerd out’ myself since he’s rubbed off on me (or … me on him I guess!)

Yeah - shows like Trek involve a whole host of technological miracles that must be allowed in order for the writers to get on with the real story line and cultural commentary they wish to pursue. But show writers are geeky enough that they don’t leave the stuff totally ‘unexplained.’

FTL (Faster than light travel) is a must if one is to be gallivanting around star systems having adventures across the galaxy - and so they have ‘warp drive’, which (to use their technobabble) - “compresses space” in front of the ship in order to allow them to bridge the great gulfs.

And to prevent them from turning into grease stains on the nearest wall every time the ship does impossible Newtonian accelerations, they have “inertial dampners”. And of course the ‘artificial gravity’ is almost always still online, even when the ship is half blown to smitherines and they have no energy left to run shields or anything else. Amazing how dependable those ‘gravity engines’ are!

And of course - the shields! Those shields out in front of the ship apparently keep the grains of dust from being a problem. Because Phil is exactly right - getting hit by a piece of sand at a fraction of light speed, say 1/3 light speed, a 1/100 g piece of sand would have about 5 * 10^10 J of energy, (and that’s just doing a straightforward Newtonian calculation for that - not including the relativistic effects of it’s increased mass, etc. which would actually make it even more energy yet!) That’s the equivalent energy of blowing up over 380 gallons of gasoline all at once (all in the impact of a grain of sand!)

So … yeah. Even without getting into all the transporter / holodeck / replicator stuff - One already has a host of needed techy miracles just to get to simple interstellar travel within reasonable time periods.

Believe me - the fans are all over that stuff. Meanwhile - the real stories are always there too. Good sci fi always has commentary of one kind or another, sometimes even quite preachy.

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Yes. Generation ship or bust.

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If y’all like sci fi , at least in USA, there is the free streaming service tubi that has hundreds if not thousands of sci fi films from the 50s to now. I use it for films like “ the crawling arm, tales of tomorrow ( series ) and things like the magnetic monster and the queen of blood. Which all of those are more on the sci fi horror side but they have regular sci fi too.

I’m really looking forward to Cixin Liu’s “ Three Body Challenge “ out of China coming to Netflix next year.

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That’s because there are no g-forces involved in exiting warp: the ship itself has not been traveling faster than light, it has been riding a wave of spacetime that is moving faster than light relative to the rest of spacetime. The actual issue involved is just what happens to regular spacetime when a distinct blob of spacetime is ripping along at superluminary velocity – an issue that peeks up in the Next Generation series when it is found that using high warp speed is damaging the very fabric of the universe.

As for Galactica, as I recall the show the ships aren’t actually in the regular universe when traveling, though I don’t remember any explanation of how the jump drive worked. And Star Wars used some kind of hyperspace – a nicely vague term!

Given the “warp bubble” version of space travel the danger isn’t to the ship, it’s to the object that’s in the bubble’s path: a warp bubble moving through spacetime would have a bow ‘wave’ and a ‘wake’, and the sheer between them would be likely to rip anything colliding with that interface down to constituent sub-atomic particles. Of course the energies involved would be immense – something I don’t recall being explored in any of the series.

This does, however, point to a different problem and that is travel at significant fractions of the speed of light, and is why one physicist calculated that velocities greater than 8% of c will be impossible because at the best possible computer speeds a course change couldn’t be initiated quickly enough to avoid hitting things that become visible ahead – and that’s for objects large enough to be detected by sensors with radii on the order of a few kilometers, when at such a velocity a grain of sand would impact with enough force to strike like a small nuclear weapon.

is meaningless since there is no such thing as “the speed of thought”. The speed of imagination comes closest, but it is instantaneous since I can imagine myself in the surf at SanDiego one moment and standing by the Washington Monument the next.
Besides which, God has no need to travel since He is already everywhere.

The danger being in accelerating since that presents the material end of the vessel to whatever is in the path; decelerating has the drive plume leading the way and conceivably turning anything in the path into plasma – not that that would make things much safer unless we postulate a drive plume energetic enough to blow that plasma out of the way!

With the original series it was bloody obvious, with dialog coming straight out of Mormon writings. But I thought the second version was independent of that.

Trek never quite comes out and explains ship’s gravity, but there are hints that “gravity plates” sort of draw their own power from subspace or some such thing, so the ones built into every single deck can’t be turned off.
Of course that blithely ignores the fact that by the time you stack thirty or more decks with all their own gravity plates that the gravity should be cumulative . . . .

how may this be explained scientifically?

when i watched the first series i was very young…my father and i made it our Friday night thing.

The second series was obviously far more recent and so as an adult i stumbled across that information from the usual reliable source Wikipedia

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What really makes this a total fantasy is the idea they can get back without much time passing at home. The nearest star is 4.2 light years away and so at the very least 8.4 years will pass at home during a round trip to the nearest star and back no matter how fast we go.

That is about a third the speed of light.

25 g is not that reasonable. A constant 1 g is the most reasonable since we need that anyway to be comfortable and healthy.

At 1 g it would take 115 days to reach this velocity.

At 25 g it would only take 4.6 days but that is 4 times the g force that would be lethal to human life for more than just a few seconds.

But we really need that 1 g force for the whole the trip to be healthy (so it doesn’t make sense to stop accelerating at that velocity), and we need to decelerate at that same force for the second half of the trip. In that case the trip to the nearest star would take 3.6 years (7.2 years round trip). Notice the 3.6 is less than 4.2 for this 4.2 light year distance. Relativity limits the speed other people see you travel and not how long it takes the traveler to get to his destination.

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I just read the Wikipedia article and I’m not seeing anything linking the second series (2004 - 2009) to Mormonism other than due to the similarities to the original that was aptly dubbed “Mormons in Space” – in fact there were complaints that it had dumped actual religion for its own strange version.

Not if they’re going faster than light, which is what warp speed is all about.
On the other hand, at low warp speeds the time passed ‘back home’ should be noticeable; if they’re ‘only’ going ten times the speed of light then that 4.2 light year trip is going to use ten months back home; at a hundred times the speed of light it will still be a month passing back home.

Except that warp drive does not accelerate the ship itself, so there are no g-forces involved.
I’m trying to recall that stats concerning star Trek’s “impulse power”, which is sub-light and therefor ought to definitely involve actual acceleration; I think that in one episode they accelerate at 10km per second squared, which is 100g and should past them all into goo dripping from the back bulkheads – so enter “inertial compensators”.

1000g, actually! Since 1g is about 10 m/s^2.

Not that another magnitude makes much difference to the still unfortunate ‘goo’ on the bulkheads. Actually, the bulkheads and ship structure itself wouldn’t be faring so well either unless it was made of some incredible material! Better keep those inertial suppressors online!

the point i waw making is that as a result of my wikipedia searching i stumbled across the fact the entire series was originally produced by mormons as an explanation of their philosophy. It wasnt meant to mean that my only source was a single wikipedia article. One should note that there are many links within that article that lead one to the mormon perspective and why the movie was made.

A member of the Church of Jesus Christ of Latter-day Saints, Larson incorporated many themes from Mormon theology into the shows.[1][2]

I probably didnt ellaborate enough on this.

Its interesting that the soviets grumbled about the original series as it seemed to incite anti soviet sentiment

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Of course, they had artificial gravity as well, so evidently had all that gravity stuff under control.

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What I have come to understand is that God, as Creator of the universe, exists outside of the universe; that is, outside of all of the space-time continuum that all of the matter and energy that ever existed in the universe is inside. So it seems to me that God created, and maintains, the laws of physics that do seem to very accurately predict how things happen in the universe He created. And it also seems to me that God is only constrained to follow those laws to the extent that God chooses to follow those laws. So God can be anywhere and everywhere He chooses to be, in whatever form He chooses. And also, God can look at His universe from any outside direction He chooses, where outside direction means any perspective in space and/or time. And, if God really knew what He was doing when He created the universe (as I believe; it doesn’t make any sense to me to believe in a God who didn’t understand what He was doing, and did it anyhow!), then it does seem quite likely that God is capable of knowing what is going on, both in our world, and in the many (thousands? millions? billions? or even trillions?) of other worlds where He created intelligent beings, even as He set up the universe so that we cannot reasonably expect to influence any intelligent being outside of our own solar system.

Only some things not everything. Some things it has proven cannot be predicted.

Why would God create laws and not follow them? Is God inconsistent? Do they serve a purpose or not? Everything tells us life depends on them and God follows them completely.

Sure, but this only applies to the Deist God who simply watches. If God participates in events, then are you claiming God is as mechanical and predictable as a clock? I don’t think so. God must choose between seeing the future and participating in our lives to alter that future. Since I am no Deist, the I believe in the God who chooses to participate in writing the future rather than simply knowing the future.

The structure of space-time indicates it is very likely we cannot.

This leads straight to the real underlying, unstated assumption: Why did God bother to create this universe, and put us into it, rather than just create us in Heaven?

If you can answer for certain every single purpose God has for every single person on this earth, then you might see that God does, in fact, perform some miracles. Or perhaps the truth is that God knew so completely everything that was going to happen that the universe can function without His direct intervention.

So why would God actually intervene in His world in a manner outside of the laws of physics? I believe He would do so if such intervention was necessary (or appropriate) for His purposes to be met. I also do know that it is almost always impossible to determine from observations whether God is intervening directly by acting outside of the laws of physics, or whether God set something in motion so precisely back at the Big Bang that He didn’t have to do anything now.

The observational facts are that any such intervention which has occurred in the recent past has occurred in a manner such that the intervention does not provide direct, objective evidence of God’s existence.

Do you understand the concept of God being omnitemporal? God knows the future, from observing it, and knows what choices we have made, and knows what He had to do to have “All things work together for good…” And once again this leads to the question of what His purposes really are for us here. And once again our modern understanding of the laws of physics that God created and maintains, that are good enough to be useful predictors of human scale events even though we don’t have any way of knowing where any single electron is, and where it is going, provides us with a way to get just a bit of understanding of how God thinks. We can predict the weather reasonably correctly without trying to measure the location and motion of any specific air molecule. And God can guide our lives to the place He wants us to go without preempting our free will, knowing all the interactions we have had, are having, and will have, and guiding the total outcome to be good for us. I do wish to note that He didn’t promise that every single thing that happens to me will be good for me, and He didn’t promise that it would be what I think would be good for me!

Bottom line, I think God knows the future, and chooses to participate in writing that future, but does so in a manner that does not preclude my free will (or that of anyone else), with the possible exception of a very few critical cases (there is not objective evidence of God regularly intervening) - since I have no way of knowing in detail what God has done, is doing, or will do, and I, for one, will not claim that I get to say what God can or cannot do.