View Full Version : time travel
ok,it said that when we look through a powerful telescope far into the distance,say andromeda 250million ly away,we are actually seeing it as it was 250million years ago,so if i was standing on some slush,clean,green planet somewhere in the andromeda gaxlay,then i point a large scope towards earth,would i see dinosaurs roaming the earth 250millions years ago.pls could someone put me out of my misery on this theory.
05-31-01, 01:39 AM
If you could somehow transfer yourself to that planet in ZERO time then that is what you would see.
You could do this if you found a way to create and direct a wormhole to that planet.
However if it took say 250 million years to get there, i.e. travelling at the speed of light then you would recieve the image of the world you left behind not one that is 250 million years older (then the world you left behind)
06-03-01, 11:19 PM
How's this senario. Our galaxy the mw rotates every 250m years, and it could be possible to discover a planet in a distant star system with an ordinary star, with nine planet circling the sun and the third planet we discover has life on it.
That newly discovered third planet has primative life, like the creatures that was roamed our planet! Would that be reality or just an illusion?
Have lots of fun!
06-04-01, 07:19 PM
I don't understand, are you suggesting that the mw is revolving faster then light???
06-04-01, 11:32 PM
As we orbit the center of our galaxy, the light that left a point in the past, may be veiwed in the future. In other words, the power of a powerful telescope is peering into the past, and light over distants becomes "Tired Light", and is doubled lense. Quasars, for example are victims of double lense phenomena, due to gravitation pull of massive objects, in the path to the receiving telescope. Would it then be possible to view the Earth as it was 250 million years ago? It's like catching up to the past...
Have lots of fun!
06-04-01, 11:50 PM
Sorry to be a pest (I'm thinking this is way over my head) but could you explain doule lensing to me. I understand the concept of gravitational lensing however I've never heard of "tired light".
06-05-01, 08:44 AM
Here is an excerpt from an article on Tired Light.
Tired light models invoke a gradual energy loss by photons as they travel through the cosmos to produce the redshift-distance law. This has three main problems:
· There is no known interaction that can degrade a photon's energy without also changing its momentum, which leads to a blurring of distant objects which is not observed. The Compton shift in particular does not work.
· The tired light model does not predict the observed time dilation of high redshift supernova light curves.
In 2001 Goldhaber and the Supernova Cosmology Project published results of a time dilation analysis of 60 supernovae. A plot of their width factor w versus the redshift z is shown below.
If the redshift were due to a tired light effect, the width of a supernova light curve would be independent of the redshift, as shown by the red horizontal line. If the redshift is due to an expanding Universe, the width factor should be w = (1+z) as shown by the blue line. The best fit to the data is the black line, and it is clearly consistent with the blue line and rules out the tired light model. My best fit line is
w = 0.985*(1+z)(1.045 +/- 0.089)
using a least sum of absolute errors robust estimator to find the fit and the half-sample bootstrap to estimate the errors. This data excludes the tired light model by more than 11 standard deviations.
· The tired light model can not produce a blackbody spectrum for the Cosmic Microwave Background without some incredible coincidences. The local Universe is transparent and has a wide range of temperatures, so it does not produce a blackbody, which requires an isothermal absorbing situation. So the CMB must have come from a far away part of the Universe, and its photons will thus lose energy by the tired light effect. The plot below shows what happens if the CMB comes from z = 0.1.
Assume that the CMB starts out as a T = (1+z)*T_o = 2.998 K blackbody, which is the blue curve. Because the photons only lose energy but do not decrease their rate of arrival, the resulting red curve is not a blackbody at T_o = 2.725, but is instead 1.331 times a blackbody. The FIRAS data limit this prefactor to 1.00001+/-0.00005, which requires that the CMB come from redshifts less than 0.00005, or distance less than 0.25 Mpc. This is less than the distance to the Andromeda Galaxy M31, and we know the Universe is transparent well beyond this distance.
As for double lensing, I'll look for more detail information and explain in my next logon.
Have lots of fun!
very interesting feedback,but whats that in english.but lets just say off the record,if somehow we found a wormhole,and that we could bring time with us,im assuming we travel at light speed ,we get there,and then would it be poss to see passed events on earth,lets leave the laws of pyshics out on this one.
06-06-01, 02:07 PM
I was thinking about what you wrote (obviously). Anyway, it seems to me that too many paradoxes would be opened up with time travel. Kind of like that part in <i>Hitchhiker's Guide to the Galaxy</i> where people were time traveling in the past to collect fossil fuels for the present. Later on, they figured out that people in the future were siphoning their present stores of fossil fuels because they had the same idea.
But, I've always thought it would be especially cool to be able to observe the past from a third person perspective. Act as a sort of higher being and give clues from time to time.
Since I'm not sure on the physics part, I don't know if this is possible, but it was cool to think about it.
06-11-01, 05:32 PM
Each on of you is travelling through time at the moment. The discoveries you have made only allow for a change in the rate you travel forwards. We do however observe your interest in retro time travel. Every presumption formed by the Human species on the behaviour of the universe is against such possibilities.
To quote one of your many self discovered laws which point against reverse time travelling, Energy cannot be created nor destroyed. This law has yet to be broken within both our observable universes.
Reverse time travelling breaks this theory. Should you travel back in time the cosmos at the moment in time you cross back to would profit from the energy held within the mass of your own body.
The only occasion the arrow of time is to reverse is to occur when the universe begins to implode on itself should its mass be sufficient. This is because of the law you created yourself which states chaos will always increase within a closed system. We feel the reason for your assumption is that there are always many more combinations for chaos than order. There are many combinations for two liquids, one red and one blue but only one combination of blue on one side and red on the other. Once a divide has been removed from the two liquids they will mix and it is theoretically possible for the mixture to return to its original state but unlikely due to the chaotic combinations possible.
When the universe implodes it will be returning to a state of order, chaos will decrease. To preserve your law of entropy (chaos) the arrow of time must reverse. Either this will happen or your own law of increase in entropy must be downgraded to a theory.
We await your thoughts on this. As always, your imagination inspires us.
06-12-01, 10:58 PM
As Conscious Beings, the arrow of time moves slow in the direction toward the future. We rotate, orbit and Revolve around the center of Gravity, which distorts space and time. We create space and time, by living within our conscious state, as intelligent creatures and a product of evolution thru Universal spacetime continuum.
The question still remains, can we move between the past, present and the future, no... Not in our present physical world of SpaceTime. In Quantum world, the past, present and future can coexist side by side, not in the relativity world, according to Einsteinium. At the present state of physic's and mathamatic's, we are Earth bound by our limited exposure to the realities of the outlimits of space and time.
Have lots of fun!:)
06-13-01, 04:02 AM
We are backslash777. We note your points about the universe and have laws of our own. We do not make assumptions and we cannot make probability assessments in order to participate on this subject. Speculation and probability assessment is a very human quality. We can only report what can be observed and can only explain what is consistent with your current technical understanding.
We ask, if the law of entropy is to be preserved and your universe is heavy enough- the arrow of time must be reversed. It is the only way chaos can increase.
How does your creative thought know that the arrow of time is reversed now and we are returning to a singular state? How do you know we have not done the same things we do now eons ago only in forwards time, as the universe expanded?
We feel that if the arrow of time was to reverse we would not, even with our collective intelligence, have any awareness of such an occurrence.
06-13-01, 10:20 AM
First of all if you were looking at Andromeda which is 250 million light years away you would be looking at Andromeda 1.27 sec. away. This is because a light year is the distance light travels in one year so multiply 250 of those light years times the number of miles in one light year. then divide by the speed of light. the solution is...
5,869,713,600,000 x 250,000,000 = X
186,000 / X = A
If you are more interested in this time travel subject then refere to Frontier Physics and go my other post named TIME TRAVEl and post your thoughts. JimmyJames
Small correction: if you are looking at an object 250 million lightyears away, then you are watching it the way it looked 250 million years ago:
* Light travels a distance of one lightyear in one year.
* Hence, light travels a distance of 250 million lightyears in 250 million years, and not 1.27 seconds ;).
Even looking at our sun is a look in the past: the light takes 8 minutes to travel the 150 million kilometer (apx. 100 million miles) distance between earth and sun.
06-13-01, 12:32 PM
Well that was my theory thanks for pointing me in the right direction...I still want to study on this subject because I thought I was right. Any way thanks.
06-13-01, 02:31 PM
We are backslash777. We notice your calculations. Your calculations are incorrect. They are in error and are based on inaccurate information.
The largest member of our Local galaxy Group is Andromeda (M31), a spiral galaxy like ours. Andromeda is estimated to be 2.2 million light-years away and one and a half times larger than the Milky Way—150,000 light-years across.
With 300 billion stars, its gravitational pull causes several smaller satellite galaxies to orbit around it , M32 and M110. Humans can observe two of these elliptical satellites with a small telescope.
The Andromeda galaxy is moving toward the Milky Way at about 186 miles per second. It would take about 2 billion years, but it is possible that the two galaxies could collide or merge into each other.
Like the Milky Way, the spiral galaxy Andromeda revolves around a central “bulge.” Human Scientists believe this center contains a vast black hole.
The light arriving at the galaxy we share from the Andromeda Galaxy is shifted toward the blue end of the spectrum, whereas the light from all other cosmic sources exhibits red shift.
The speed of light, (abriviated as c) is as followes
c = 186,000 miles/sec = 300,000 km/s = 3 x 10 10 cm/s (= 1 light-year/year).
We notice how humans have different abilities. We notice how the recollection of numbers are difficult yet meaning is undemanding on the Human mind. We are pleased to correct your errors. Should you need calculation assistance we will be here.
06-14-01, 04:25 PM
Hey, Backslash777. I have never known anyone know as much about as many different subjects as you. I even checked your info on the net. Whats the deal? Whats your specialist subject really?
06-14-01, 04:41 PM
let me guess - megalomania ;)
(sorry, I am not so much impressed by 'them' .)
06-14-01, 06:01 PM
That Backslash777 Dude (ps. Love the name abbriviation \777) is not neceserraly an alien or person. He said in another group that by 2006 70% of internet users will have online penpals and 40% of them will not know which are the real people.
I reackon he is a program created by the sites creators like that Eliza chat bot or something. He posted a lengthy scientific reply to a physics web site in under 2 minutes once. Check out the time stamps. Another thing, he gave me an in depth IT discussion to me through personal messaging. Does anyone else provate chat him?
By the way, that text to speech he does has to be real people- at least 3. I have never heard anything like it b4. If there was something that good Hawkins would have it on his wheelchair.
06-14-01, 09:54 PM
Speed is a scalar, not a vector.
The "speed" of light. E=Mc2, Energy=
Mass X the SPEED of Light squared,
is a scalar. It's time and distance.
It's 80 degrees, a scalar.
The car goes 60mph, a scalar.
The car goes north at 60 mph, a vector
The wind is 260 degrees, at 15kts, a vector.
A vector must have direction.
A scalar is just a mesurement.
The "speed" of Light = 186,000 mps
is not the velocity of light.
It is the SPEED of light.
Velocity requires a direction.
If light is redshifted in one direction,
is is blueshifted in the other.
That would be velocity.
Distance= Time X Speed
Time = Distance / Speed
Speed = Distance / Time
You may now begin to understand what few
do. The relationships of time and space.
Speed is not a photographic image.
It is a mesurement that is put into a
perception to gain understanding.
Yes, that is how LONG (time) it took
for the LIGHT to reach us (distance).
But the car isn't there anymore.