Question

I once saw a science documentary, in which a well known presenter talked about travelling to another star, let's say 100 light years away, (I forget the actual distance) He explained that that would mean, even if your spaceship could travel at the speed of light,which is the fastest possible speed, it would still take you 100 years to reach the star. Was he right ?

Answer 1

Uhm I think so. I don't know if this relates to the Einstein's theory of relativity

Answer 2

yes i think you are right

Answer 3

It is correct. The time is the time that we on Earth would record.

Answer 4

Ah yes, but the programme gave the impression that an astronaut would not live long enough to reach the distant star.

Answer 5

If human can be born in the outer space, then his grandchildren can reach the star.

Answer 6

You know dragon balls my brother watches that show

Answer 7

@tbing No

Answer 8

Yes, I watched almost all versions.

Answer 9

Now traveling at light speed in theoretically impossible because it would take an infinite amount energy. But if it where possible to approach the speed of light say 0.999c then the time experienced by the traveler would only be about 4.5 years. His time slows down more the faster he goes.

Answer 10

@gleem I agree that time will slow down. However, the energy we need is finite since there is no friction

Answer 11

Yes, so as long as the engineering department can build a ship with a decent top speed, the astronaut can get there as quick as he likes.
But, it is still the case from the astronauts point of view that nothing can travel faster than the speed of light, and so as he looks out of the cabin window he sees the universe flying by, at almost the speed of light - how is it that he is able to reach the distant star so quickly ?

Answer 12

the above was in reply to gleem

Answer 13

The problem is that as the speed increases so does the mass as the mass increased you will need ever more energy to go faster. The fuel become more massive. you cannot carry enough fuel.

Answer 14

@gleem Agree that the fuel we need is incredible. One more problem is how we will stop a spaceship moving at the speed of light. We will need an equal amount of energy as we accelerate the ship

Answer 15

The programme gave the wrong impression.
From the point of view of mission control, the spaceship's clocks will slow down as the rocket speed approaches the speed of light, so the astronaut can reach the destination in much less that 100 years by his reckoning, even though he cannot travel faster than light.
On the other hand, from the point of view of the astronaut, as the ship accelerates, the spatial dimension in the direction of travel actually shrinks - when he looks at his watch it appears to be working normally, but the distance that he has to travel to the 'distant' star has decreased, so that, again, he can complete the journey in less than 100 years.

Answer 16

You see that also a problem. How do you stop something with infinite inertia.

Answer 17

Yes, it would take 100 years - 105 if you do it at 5% slower speed. lol Yes, it would definitely take a lot of energy, and a lot more to stop - so you better slower your speed to 80% of light "120 years". Warp is possible, but both questions lead into something I asked yesterday. I also found a new question that I haven't posed on anyone here. Do you believe that time slows down due to relative speed, and what brought you to that belief.

Answer 18

@biggdaddymiller I do believe that time slows down. It depends on the reference system you choose. Theory of relativity was proved right, and it hasn't been proved wrong. So that's what scientists accepted and have been using.

Answer 19

A moving clock runs slower than a stationary clock. It has been demonstrated with the ultra accurate "atomic clocks" placed on a jet. Also it is observed that unstable particles with different energies and therefore different speeds have different mean observed lifetimes consistent with special relativity.

I might add also that time slows down as gravity increases again demonstrated by the atomic clock at points at different altitudes.(earths gravity is less at higher altitudes .

Answer 20

Exactly

Answer 21

So, like I asked yesterday.......

Answer 22

Is time an effect?

Answer 23

Or is it a physical property?

Answer 24

Time is a coordinate in a reference system that is used to label events.

Answer 25

What event is it labeling?

Answer 26

A property of what? certainly not a object . Einstein seems to think it is a property of space , like distance, since we introduced it as a "coordinate" for this theory.

Answer 27

Any event, such as a rocket motor firing, or a spaceship landing, or an atom emitting a photon, whatever.

Answer 28

can you define position?

Answer 29

If space is not an object, then what is it?

Answer 30

It's hard to say. We usually accept time as an effect. However, in modern physics, time can be a physical property

Answer 31

I am friending you ALL! This is EXACTLY the type of people I need to be around!

Answer 32

give an example of time as a physical property.

Answer 33

@biggdaddymiller You too. A potential member of Openstudy

Answer 34

Hmmmm.......good question. The difference of time degradation in a black hole versus what some would call "Normal Space".

Answer 35

http://www.onenesspentecostal.com/einsteintime.htm

Answer 36

RE: http://www.onenesspentecostal.com/einsteintime.htm

Is distance real?

How much does distance weigh?

The validity of any physical theory depends on its agreement with observation. Where Relativity is concerned from all verifiable properties He is batting 100%. It may not be correct though but until proven otherwise it is.

Answer 37

Ok, what if - partially, I agree with this site you sent me to, AND Einstein. Do you see the conclusion from the site as correct, and in what way do you believe?

Answer 38

I REALLY want to say thank you to you guys. I am really having fun! SO MAKE LOOK STUPID PEOPLE! It doesn't take MUCH does it?
lol

Answer 39

Make ME look stupid. lol I am doing a good job on my own.

Answer 40

Sorry. I think this article considers about time more philosophically than scientifically

Answer 41

Sorry, I didn't meant to waste your time. This was fun though. Thanks

Answer 42

@biggdaddymiller You are good. The problem makes me think a lot

Answer 43

Quote: 'The only justification for our concepts and system of concepts is that they serve to represent the complex of our experiences; beyond this they have no legitimacy. I am convinced that the philosophers have had a harmful effect upon the progress of scientific thinking in removing certain fundamental concepts from the domain of empiricism, where they are under our control, to the intangible heights of the a priori. For even if it should appear that the universe of ideas cannot be deduced from experience by logical means, but is, in a sense, a creation of the human mind, without which no science is possible, nevertheless this universe of ideas is just as little independent of the nature of our experiences as clothes are of the form of the human body. This is particularly true of our concepts of time and space, which physicsists have been obliged by the facts to bring down from the Olympus of the a priori in order to adjust them and put them in a serviceable condition.'
The meaning of relativity, Albert Einstein.

Answer 44

And that is why I loved him as a scientist, and a philosopher.

Answer 45

Time is physically significant as well a philosophically interesting. Physics is not necessarily devoted to explaining why thing are but more to How things happen. Time is a quantifiable measure of how changes occur. Just as position is intuitive (how do you define it without assuming its properties? You will not that changes (what is change) incorporate both position and time. No change in position no time, No time no change in position.

Answer 46

Especially in this day, and age the advent of virtual information has provided us with ways of thinking about something without having a clear perception of what we are trying to think about. Only that we pursue what we do not know, and carry on.

Answer 47

Please define Virtual Information.

Answer 48

I'm making up something - I think, or rather I have been. Is it alright if I use this term?

Time-perception = Tp = (toilet paper ; p)

Answer 49

This is becoming out of hand. Good Bye

Answer 50

Just dealing with software, data, Telecommunications, and our uses of them.

Answer 51

Not a happy ending :)

Answer 52

Sorry if I've offended you.

Answer 53

I'll learn more. Maybe I was wrong. "A little knowledge is a dangerous thing."

Answer 54

Very little. lol