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Kaustubh Katdare • Dec 1, 2005

# Time Travel - Is it Possible?

Note# Ideas presented here aren't mine :? , just read them somewhere π²

This question has popped up in my mind so many times. I read somewhere that it is possible! This is how.
Some scientists have discovered that the light waves never die out. Assuming this is true, we can safely say that, at any particular moment, the light rays are beamed into space from all the objects (provided that there are no obstacles in their path).

Now let's say we device some way which enables us to capture these waves! Boom! we'll be able to see the things happened in past!

Well of course we may have to travel faster than light to capture those waves & according to Einstein, this is impossible.

-The Big K-
rick • Dec 6, 2005
Time Travel Is Not Possible

I think time travel is not possible π

I remember one of my Physics professor saying no object in the world can travel faster than light. Because as any object approaches speed equal to "C" (the speed of light), its mass approaches infinity. So at the speed of light, an object will have infinite mass :shock:

That makes it an impossible phenomenon. I'm not an expert on this topic but could gather some stuff from old physics lectures :wink:

I guess I'll keep my mouth shut and keep an eye on this thread.

rick
odwan • Dec 19, 2005
can`t agree more

hi ...
i can`t agree more with rick....
i`ve read it some place... there ae no material in the world that can run or go at speed of light and still have its material shape without changing anything inside it...

u can think on the other direction... if a time machine has invented yesterday then u can travel in time but between yesterday and today. if we agree with that then the day u will see ur self but older then u can say a time machine has been invented, this is an idea of "if we invented a time machine, so in some place in a cirtan time u will have two body with the same person(duplicate but one older) and that is not posiible" .

few days ago afriend said to me: Eddie, if u run very very fast around a tree approching speed of light u will see ur ass ...( iam sorry for bad words )
hahhaha

nice subject...
that`s a small idea from my small brain...
have a nice day The_Big_K and rick ...
owaisg53 • Jan 5, 2006
Hi! All
i dont think it is possible in present circumstances and technology, but in future if we can find the required material from other planets ...

May be good project for our grand childrens..

Hahaha
Owais
rick • Jan 5, 2006
Re: can`t agree more

odwan
few days ago afriend said to me: Eddie, if u run very very fast around a tree approching speed of light u will see ur ass ...( iam sorry for bad words )
hahhaha

nice subject...
that`s a small idea from my small brain...
have a nice day The_Big_K and rick ...
Eddie, you are right. If you run with speed approaching that of light, you sure will see ur ass π . Remember that you can never attain the speed of light. Because at the speed of light the mass of any object will be infinite!
rick - having a nice time already π
PoliBr • Jan 12, 2006
other possible approches

First, a strongly believe that anyone who would join such a forum -Crazy Engineers-, have to belive even, if just in wishfull form, in time travel.

I have no problems in agreing that the speed of light approach will lead to nowhere, I recall that when lim speed -> C , mass -> 0, hence if you aren't a ghost don't go buying you time travel-tickets just yet.

My point is, if this dosen't seems to work, try looking for a new aproach. And believe, there are quite few others. For example Worm Holes. A wormhole is created somehow. An object that goes into one end would come out of the other end in the past relative to the time when it enters.

The energy requierd to built a wormhole big enough for a spacecraft is bigger than the sun's. And we would need some of a still theoretical "exotic matter". We are not even close to such technologies. But is a good way to get around you speed of light problem.

I'm sure there are many other possible approches yet to be discovered. But there are a few known suggestins that we should borrow from physics, the wormhole is just one of those. So, it's way to soon to say that it is impossible.
Jerry • Jan 12, 2006
Agree π

I recall that when lim speed -> C , mass -> 0, hence if you aren't a ghost don't go buying you time travel-tickets just yet.
Well, lim speed -> C (speed of light) , mass -> infinity , size of object -> 0 .

So at the speed of light the mass will be infinite and the size of object will be zero. I guess the time will stop for the object under such conditions.
sarakhursheed • Jan 19, 2006
What's the shortest distance between two points??

A straight line !!!

No......If we turn the page then there 'll be a shorter path n tht's the concept of a worm hole

what I just narrated is what i saw on TV some guy was explaining abt the time travel.....so tht's the example he gave...I found it very interesting tht's why shared it here..

Wat do u ppl know abt worm hole can any one tell me.....cuz my knoledge is very limited abt it.
hi guys,

For me time travel is not possible, as we understand physics today.

The fact that no body would exceed speed of light was established with morley-michelson experiment, which laid the foundation for special theory of relativity.

According to newtonian physics application of force to a free body should accelarate it. And constant force means contant accelaration until you meet the damn speed limit.

So what does the force appiled do than. Unfortunately law of conservation of energy plays spoil sport. So Einstein tried to accomadate these three limitations.

This can be adjusted in different ways.
1. F constant, A almost zero so M almost infinity.(F=MA)
2. F constant, M constant, Change in velocitiy almost 0, so t becomes almost infinity. means 1s takes infinite time to complete. In other words time stops.(F=M*delta(v)/t)
3. F constant, M constant, (time)^2 constant, so distance X approaches zero(F=M*(delta)X/t^2).

From point 2, its deduced that time could be stopped in a relative frame.

Only time travel that would be possible would be in a frame which is faster relative to another frame, so time there moves relatively slowly. After a few years if you change to slower frame you may find people born along with you might have lived few more years extra and are older than you.

So no theoritical chances of travels in future or past. At the best you can hold on to your moment while others don't.
hi sarakhursheed,

The "worm hole" is an energy field which in theory could connect two different frames moving at different velocities.

In slower frame time moves faster and in faster frame time moves slower.

Say good bye to all your friends in slower frame and jump into the hole. You will end up in faster frame. few years later you may pay them visit again and ofcourse you need not spend much on travel. just jump into hole and you might be surprised to see much older friends then they were supposed to be.

Kaustubh Katdare • May 5, 2006
more thoughts?

a healthy discussion going on here.

more ideas! anyone? π

-The Big K-
The_Big_K
a healthy discussion going on here.

more ideas! anyone? π

-The Big K-
I am still puzzled that How one can say that spped more than light is not possible...You should say its not done till now...
before 25 years...people must have thought that spped more than sound is not possbile but it is possible isn't it...
whoknow after 26 years speed more than light too.....

--Crazyπ
Kaustubh Katdare • May 9, 2006
I do agree with you CrazyBoy. Stuff which looks impossible today, will be a reality tomorrow.

Few months ago, there few scientists succeeded in slowing down light. Indeed a big achievement.

Who knows but in future, the little mobile phone in your pocket will be able to take you to moon in a second. π

-The Big K-
The_Big_K
Who knows but in future, the little mobile phone in your pocket will be able to take you to moon in a second. π

-The Big K-
Wild thinking........but its great....atleast we should think that much greatπ--Crazy
Kaustubh Katdare • May 10, 2006
Of course! What's wrong in thinking 'Crazy' ? That's why we call ourselves - Crazy Engineers ( a.k.a CEans )

Now, We need more people to drop into these discussions and add some value to the thread. Let's generate more ideas.

-The Big K-
The_Big_K
Now, We need more people to drop into these discussions and add some value to the thread. Let's generate more ideas.

-The Big K-

I know the meaning of it...
but is it possible...

Shout people...

No jabberings please...if you know...than only shout..π

--Crazy
Kaustubh Katdare • May 13, 2006
CrazyBoy!

How about a new thread on Telepathy? I'm sure its an interesting topic to discuss.

I'll start a new discussion thread.

-The Big K-
crook • Jun 16, 2006
there is a separate thread for telepathy. keep this discussion reserved for the Time Travel !

pradypop's explanation was really good. I guess he isn't around since long.
hellmate • Oct 7, 2006
Time travel is possible whn you travel with speed of light.
Increase of mass is relative to ext observer. The one travelling would never realise the difference. Only that the length will contract in his line of motion, that too relative.

Time travel to future is possible because it will not alter the event chain that is leading to your present.
But travelling to your past may lead to alteration of the event chain that might hav led to your existense.
If the past is tampered with, there may be a chance that the event chain that created you never initiates and your parents never meet.
So you are never born and if you are not born then you never travel back in time.
So it is not allowed by Logic that you travell in time...
To put in straight terms...
You cannot alter your past, and whats done is done.π
xheavenlyx • Oct 7, 2006
Agree with hellmate and a few others. Time travel first has to be defined properly!!!!!!!!!

What do you mean? Travel like physically or just view the events? I cant talk about 'view' part since yes if you travel a lil below the speed of light time slows down and yu can see what your ass was like a few secs back, but

physically trveling to the past is not possible at all! Thats because, as hellmate put it. Its not important that you have to kill someone to alter the past, you just have to exist! moving a single air molicule out of place can ccraete havok! Its called the 'Butterfly effect'. A butterfly fluttering in cal, US can cause someone to die in India. Make the connection yourself. π

Regards
Nickhouse • Oct 24, 2006
Time travel has already been done in the 1950s or 60s. 2 atomic clocks were used, 1 stayed an the ground, 1 went up in a plane. After some time flying around, the plane landed, the 2 clocks compared, and they were a few nano secs. out helping prove the theory of relativity. But you can only go back in time by traveling faster but I suppose that you could argue that the clock on the ground went forward in time ...........
Kaustubh Katdare • Oct 24, 2006
Nickhouse
Time travel has already been done in the 1950s or 60s. 2 atomic clocks were used, 1 stayed an the ground, 1 went up in a plane. After some time flying around, the plane landed, the 2 clocks compared, and they were a few nano secs. out helping prove the theory of relativity. But you can only go back in time by traveling faster but I suppose that you could argue that the clock on the ground went forward in time ...........
There you go, Nick! π

Your post reminds me of "The Twin Paradox" ! I guess 'Brief History of Time' has the best explanation of the phenomenon.

Btw, do we have any neo idea of a time machine (which actually travels through time, back & forth)? π

-The Big K-
aashima • Oct 25, 2006
Well it seems impossible to know that time travel is actually possible but even that too is a true notion that something which we can't even think of today will possibly be present in the near future.
But considering the scenerio of today, I don't think it will be possible. Competeing the speed of light is not a child's play and its a topic that has been pestering the scientists who have been trying to turn time travel to reality. And even if we somehow manage to travel faster than the speed of light, job after that i.e. to capture the required waves of one's past doesn't seems that feasible.
Ankita Katdare • Apr 17, 2011
The_Big_K
There you go, Nick! π

Your post reminds me of "The Twin Paradox" ! I guess 'Brief History of Time' has the best explanation of the phenomenon.

Btw, do we have any neo idea of a time machine (which actually travels through time, back & forth)? π

-The Big K-
[It's amazing how most of the great thoughts are discussed on the forum previously]

For those who are unaware of it, read what a twin paradox is: Twin paradox is an experiment in special relativity in which a twin travels into space in a high-speed rocket and on returning home to finds he has aged less than his identical twin who stayed on Earth.
ISHAN TOPRE • Apr 17, 2011
Yup, Biggie, I know about time machine. I will try to explain it to you. But time machine to travel in past is not possible.

I will post a whole story about it in my own words. Actually I used to read about it a lot a until few years back.

Till then watch this video.

i definitely answer as yes if we able to manage to travel faster than light
Ankita Katdare • Apr 17, 2011
narayana murthy
i definitely answer as yes if we able to manage to travel faster than light
@narayana: We are looking for reasons for our statements. π
ISHAN TOPRE • Apr 17, 2011
@narayana: We are looking for reasons for our statements. π
Hmm... I did't wanted to tell but it seems that I will have to.

Suppose Narayan is a great scientist and he luck by chance invent a time machine which can travel to past. Clear?

Now Narayan becomes mad. He goes to his past and kills the Narayan of his child hood. So wht will happen? The Narayan in future will also die because the childhood is dead. Clear?

But if narayan from future is dead, then who will kill the Narayan of child hood? No one.. So Narayan is alive of both child hood and Future.

Now this is contradictory " Narayan is dead at the same time Narayan is alive"

So that is why time machine travelling to past is not possible.
Ankita Katdare • Apr 17, 2011
This is what is the Twin Paradox is all about. You must've heard about 'parallel universes' So, it might be possible that narayana from one universe can meet the narayana from another universe when he travels in past.
ISHAN TOPRE • Apr 17, 2011
Whatever I mentioned just now, Stephen Hawkings calls it Grand daddy rule or something like that.

Twin paradox is mentioned in a Marathi book by Jayant Naralikar called " Akashashi jadle nate"
ofcourse but friends that theory was proposed by einstein
upto my knowledge we can travel if we travel faster than light because all are happening due to light falling on earth and even on us
@ishu: lol yes we will die if you travel to past but the past is not changed so if we come to present we will be alive
in case if we are able to change past then there will be change in present and further in future
if we change anything in future it doesn't effect now
as we never seen a people from future so we are thinking there is no time machine invented
but why cant we think we cant see the person travelling and seeing us was not visible to us
anyway it is opposition to ethics if we invent such a machine we can do everything but i think we can see future but not travel because human mass can't be travel in such a fast and we cant resist it too
so if the technology develops in this rate in upcoming 50 years we can see time machine by my estimations
Guys, have you heard of John Titor??? He claims to travel time and he is from 2036. π Just found out from Wikipedia and got interested when I saw the movies, Back to the Future... π All the three parts were interesting! π
John Titor - Time Traveler
John Titor - Wikipedia, the free encyclopedia
ISHAN TOPRE • Apr 18, 2011
Clear your knowledge people, I will tell you what twin paradox is. We have two twins CP and CT. Both are bright students and great engineers. So what do they do?

CP likes her friends and wants to stay with us on earth while CT likes to travel. So CT builds a space shuttle which can travel at a speed faster that that of light. CT sets out for her journey.

When CT sets out on a journey both CP and CT are of 21 years.

When CT returns after a few years lets say 100 years so tell me

1. What will be the age of CT?

2. What will be the age of CP?

I will tell you the answers only if you people try for that answer.
Ohy!!! Both will be dead by that time!!! Is 100 years, just a few years for you??? π

Oki, cutting the kiddings, CT's age will be definitely lesser than CP... But theoretically, CT's age will be 21...
CT's Age: 21
CP's Age: 121
ISHAN TOPRE • Apr 18, 2011
Well I will just say that you are on a right track but the answer is still not correct.

I don't expect correct answer but I want the reason behind it. ( Hint: The answer lies above us all)
Yeah, right... My answer is not right... But, to calculate it, age of CP is right I guess... But age of CT is at 0 mps, it would be 121... Whereas at 299792458 mps, her age will surely be less than what it is...
Dude, the concept is Twin Paradox. CT cannot for sure travel at the speed of light. So, considering the lorentz factor, Ο΅ = β(1-vΒ²/cΒ²)... It comes around, well, 0.5 * 100 = 50 years... π Am I right???
The_Big_K
Note# Ideas presented here aren't mine :? , just read them somewhere π²

This question has popped up in my mind so many times. I read somewhere that it is possible! This is how.
Some scientists have discovered that the light waves never die out. Assuming this is true, we can safely say that, at any particular moment, the light rays are beamed into space from all the objects.
Now let's say we device some way which enables us to capture these waves! Boom! we'll be able to see the things happened in past! -The Big K-
You are right. The only device you need is your eye. When you look at the moon you are seeing what happened about 1.5 seconds in the past. When you see proxima Centauri you are seeing about 4.2 years back. The problem is with physical travel into the past. This involves speed faster than light. The paradox is that if you go back only in time but remain on earth, you can see a younger yourself. If you decide to bump off that you then which is the you that did the time travel? Thankfully physical travel in time alone is not on.

Bioramani
ISHAN TOPRE • Apr 20, 2011
Well you are great Praveen, I mean I won't tell you calculations but I will try to explain you all in my own words what is the theory.

In case of heavy objects, the time slows down. In simple words Time will be slow near sun and comparatively faster near Earth. There is also one law which states that nothing can travel faster than light.

Suppose we build a space craft which travels at speed of light and Mr. Praveen is a passengsr in it. Mr. Praveen :razz: travels with a velocity of say 1 Km/ Hr inside that rocket. So what will be the actual velocity of Praveen bhai?

It will be greater than that of light, correct? So to avoid that time makes itself slower. In other words time flows at a slower speed. The resultant would be Praveen will be more slower as compared to people on Earth.

Same is the case with CT. As the time around her will be slower so she will stay younger.

What say?
Awesome man!!! That's what even I said... π