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The Science and Physics of Back To the Future
overthinkingit writes "A scientist has tried to apply serious math and physics, including the Law of Cosines, to analyze how the DeLorean in Back to the Future travels through both Time AND Space: 'in order to pull off the kind of time travel we see in the Back To The Future trilogy — the kind where the traveler is transposed in time, but remains stationary in the same relative position to where he/she left — the DeLorean would have to be an outstanding space ship, in addition to its already laudable work as a time-ship. According to Doc Brown's stopwatch, Einstein the dog travels precisely one minute into the future on this first jump, arriving, relative to their frame of reference, at the same location he left. But how far has this reference frame itself traveled during that one minute?'"
how it leaves tracks of fire on asphalt? Or in the air? Never quite understood that part. The rest of the movie, OTOH, makes perfect sense.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
The universe really DOES revolve around the earth in the movie universe, so no special measures are necessary beyond "simply" moving in time.
Since it was in space for 0.0000E+999 seconds, i.e. never.
It did travel in time and moved from one point to another in the universe (to stay in the same spot on earth) but it didn't "travel in space", hence no need to be a spaceship.
This explains the problem that I have trying to use a stasis field in place of a refrigerator. Every time that I shut down the field the food comes flying out of it real fast! (but fresh)
I'm an American. I love this country and the freedoms that we used to have.
First off, there are WAY too many pages to this article for me to read but it looks fun so maybe later.
But in regards to this, I would like a physicist to boil large problems down to "We can't do X because of the simple problem of Y." Example with Mr. Fusion: We can't do Mr. Fusion because the amount of energy that goes into creating the conditions for fusion outweigh the amount of energy produced. That's something measurable and approachable to me, a starting point.
If it comes down to the problem requiring a Free Lunch, I'd probably give up early--I'm not one to disobey the laws of thermodynamics.
In middle school I devoted large amounts of time and reams of paper to developing a formula f(n) to produce the nth prime number (at the time I was searching for O(1) oh how naive I was about mathematical induction!) and it was all because a teacher explained how powerful such a formula would be for encryption and many other things.
While I (obviously) never solved it, I sure the hell enjoyed the simplified form of a much more complex problem. And on top of that, it kind of set the tone for computer science in my life. Could hoverboards & time machines turn a movie goer into a physicist? Maybe not often but it happens.
My work here is dung.
What you fail to grasp is that the 7th dimension works like quantum sticky tape to hold you in place relative to the things around you as you travel through time. So, you don't really need a space ship because of the relativistic affects of the items around you relative to each other pulling you along. Plus there's the whole inertia thing which requires you to go 88 miles an hour exactly so you always wind up where you started whether you go forward or backward. Try it yourself by drawing two 8's. On is for space space and the other one is for time space.
Also, don't forget that the velocity has to be in miles per hour, because the metric system is gay.
DUH!
The fire was probably due to a well known fact that DeLorians leaked fuel and oil badly. That's why they quit making them.
Engineering is the art of compromise.
Um, you really don't want to go off on a tangent because the mods will mark you off-topic. I can see the sines in your post of that happening.
anyone that has (in the past) managed to create a time travel device and has tried it, probably thought they made a disintegration machine, because anything they sent back or forward in time was never seen again. (or before, I suppose)
Because a second/minute/year/millenia ago that spot was occupied by empty space. The earth is moving very fast through space.
I've always used that reason to concede that even if we DO make time travel possible, it will be of little practical value.
Then there's the other snag of transposition... if you say, send yourself back in time, what happens to that volume of space where you arrive? Is it destroyed? And what fills in the void where you left? Or one more expected result is it's transposed with your time's space. Thus all time travel is time swapping, something goes forward and something goes back. Now lets say you do make a time travel machine, and test it without considering the earth-travels-through-space issue... that means whatever you send out, you get a big ball of vacuum back. If it's a very brief travel, you may get a chunk of earth, high pressure ocean, or more likely, high pressure magma. Ouch... hope you got insurance. That'll turn your lab into a disaster area real quick.
There are so man "problems" with time travel, that it really doesn't matter if its possible or not. It's not useful.
I work for the Department of Redundancy Department.
as serious math?
Did a communications major write this?
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Reference frames don't travel with respect to themselves. By definition.
However, you could say that we're that much closer/farther from Vega, or in a different season in our Solar orbit, or in a different timezone, etc. Or the Earth's core has counterspun in relation to its own crust. Or tectonic shifts have occurred.
Just assume the car is locked onto a specific reference frame, such as a given latitude/longitude relative to the Earth's axis of rotation and the nearest large mass: the Earth's crust under the car. And pass the popcorn, it's a movie for chri'sakes.
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But how far has this reference frame itself traveled during that one minute?'
Relative to what? Relative to itself, it hasn't traveled at all. And since we don't know the mechanism for time travel, there's no reason to use any other reference frame. Really, until we understand how they are supposed to travel through time we can't discuss the interactions of reference frames across time skips.
ceci n'est pas une
Since Professor Brown is obviously using Steampunk technology (look at the ending to the final BTTF), it seems clear to me that the solution to this problem is that the Time Machine is carried along in the Earth's "Aether Drag", the distorting effect that any large mass has on the Luminiferous Aether!
1.21 Jigawatts: the energy output of a man dancing a 1.21 minute jig. So next time you jig, be very careful to dance either more or less than 1.21 minute, lest you suddenly go back in time to the 1950s where your dad is a spineless wimp.
Of course, even though the wire itself can be the same size, it'll normally look a lot thicker, because 1.21 gigavolts requires pretty serious insulation.
The universe is a figment of its own imagination.
Wrong, as you can CLEARLY see, his server doesn't have the 1.21 Jigawatts necessary to jump OVER the slashdot effect and into your browser.
These kinds of considerations aren't anything new, and injecting them into soft sci-fi like Back to the Future is a waste of time. BttF is enjoyable, though, and does make a great accidental (?) satire of the American dream and hubris. For science, read some Larry Niven or Stanislaw Lem instead.
For example, Vernor Vinge did something like this, involving teleportation. A teleporter could control both the outcome position and velocity, but velocity was "harder" and took effort proportional to the difference in velocity.
Therefore, long distance teleports were only feasible along a longitude, and to the opposite latitude, since you had to match momentum or die by either being crushed or flung off into space. The earth's spin matches at lat X long Y, and lat -X long Y, but nowhere else.
As a result, one of the world's superpowers controlled both semi-polar regions, alternating by season; while the other stuck to the equator.
"They were pure niggers." – Noam Chomsky
Fail!
It isn't the trip that causes the slowed aging, it's the acceleration. When you get back, all your classmates are going to be dead, and you'll still be 25.
-- Give me ambiguity or give me something else!
Distilling down time travel for the masses requires some dumbification of the minutia. Did you see "Primer"? Excellent, but required a flow chart. That's why the BTTF series was more popular.
Help fight poverty: Punch a poor person.
here's the link I forgot...
http://www.delorean.com/
There is no absolute frame of reference in space or in time. By taking into account the motion of the Earth around the Sun and around its axis, he is arbitrarily picking implying the heliocentric-ecliptic coordinate system is the absolute frame of reference.
To be honest though, I can't suggest a better way of doing this. The DeLorean can simply pop out of existence in one spot in spacetime and pop into existence at another. If this ability is a given, I'm not sure its necessary to treat travelling through space separately.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
Professor Brown explained that Einstein simply 'skipped' over that minute and arrived in the same place at a different time. The DeLorean -and hence Einstein- still had their combined velocities of the reference plane (place) that it had when it did the 'timeskip'; that's why it was still going eighty-eight MPH when it reappeared one minute later. If the combined velocities of the 'time traveler' or the 'place' do not change during his trip, then he simply arrives in the same 'place' just at a different time. However, if the 'place' from which he leaves encounters a sudden change of velocity at the exact moment of departure, then he could return in a very different 'place' upon arrival.
Sig this!
I call AC. ACs don't get to call BS.
I'm an American. I love this country and the freedoms that we used to have.
While it isn't BTTF, exactly, the tv show Seven Days had a similar time traveling premise, however the portion of the machine that traveled back in time wasn't the time machine itself, but rather a pod that had to be guided back to the earth. The intro of the show even shows a lost pod floating out in space with a (dead?) pilot. One of the few, if only, shows I've ever seen that addressed the time/space issue.
Ask this guy instead.
Sometimes I think our understanding of space is even more shaky than our understanding of time. It should be obvious, for example, that distances can only be measured between two objects. So saying that the time ship would need to travel a considerable distance in order to be in the same place is actually rather silly. The distance traveled in space (if that really is distinct from time) is zero if you measure it in any sensible way.
Why would you measure it from some fictitious "stationary" point in space? What does the word stationary really mean in this context? Would it be important in any physical sense?
Are you saying Earth is an inertial frame of reference? And that we would end up at the same place in a different time?
Or are you saying, Earth is not an inertial reference frame and that it would move out from underneath you?
One last thing: Sometimes I wonder; "Is that someone's signature? Or do they type that at the end of each post?"