I posted this in the astro podcast forum but this topic seems to have a lot very smart people posting so this must be the best place to have my thoughts tore to shreds

Welcome to BAUT, Alexander!

I've moved your question from the Twin paradox (relativity) thread to its own thread, where it might get more visibility.

I agree that there is something special about time, but I think of it a bit differently. I see the fundamental constraint when we start thinking about space and time is the concept of time, which starts with a simple definition. What we call a second is everything that can happen in a second-- that's it. This is just a definition that works for us. There is simply no such thing as "the rate that time passes", any more than there is a "rate that the words in a book appear on the page". A word is a word, and a second is a second, and we can perceive that word or that second any way we like, and it is still one word or one second. The rate of flow of time is a tautology, that's why it sounds like "1 second passes in one second".

However, if we do insist on thinking in terms of a rate of time passing, we attribute a speed to that rate, which is just that tautological speed of 1 second per 1 second. But now we need a concept of distance to explain why different clocks can start and end at the same place having different amounts of time elapsed on them in the process. The concept of distance also made sense of a lot of other things involving causality, and the way more distant things tend to have influences on us that are weaker and come later. So we just introduce the concept of distance to make sense of these facts, because something has to be missing if all we have is time and an invention that it flows at a certain rate.

The punchline is, when we insist that time passes at a rate we call 1 second per second, and we introduce the definition of distance (given by the way we decide to measure it), then all of a sudden reality hands us a connection between time and distance: the speed c. That comes from reality, not from light-- it would be there even if there was no such thing as light. Then physical meaning emerges from several points:
1) everything moves at c through spacetime, which stems from the tautological 1 second per second-- but if they are not stationary relative to the observer, we may imagine the "movement" is partly through space instead of entirely through time, and we need a conversion factor c to make sense of that association.
2) the paths between two points in spacetime do not cover the same spacetime distance, it depends on the path.
3) the way we measure distance and time generate an invariant, called proper time, that can be imagined to be both "real" and objective.
4) everything else we think is going on is just make believe, and stems entirely from our arbitrary way of globally coordinatizing measurements that we can only make locally.

I think you are stuck on the concept of “space-time” when you should be thinking of “space” and “time.”

A pendulum on a pendulum clock moves back and forth through space, but it moves only forward in time. You drive back and forth to work in two different directions in space, but you always do so in only the forward direction of time.

Yes I understand I think, but I think also it cant just be space the pendulum the moves through, it must be space-time as space without time would allow for no movement and gives us just fixed dimensions of volume, and if we add a second pendulum but moving at the speed of light away from the other then not only do we change the space between each we also change the position of each object in the general flow of space time , but even each object still experiences travel through time at the speed of light (60secs a minute etc) .

A simpler way to explain it is if both pendulums have a finite lifecycle of 10 day's no matter what and we attached timers to them again anything we do in the general flow of space-time relative to each other will matter not both will fail after 10 days of life relative to them self’s, and the hope of extra time or a longer life for the fast traveller because it seems to have lasted longer is just an illusion of observation.

This is my problem with time …I am told it is space-time and it is only relative to me but in the same statement it tries to say it is also a force which is general through out the universe and can be manipulated between 2 objects, yet oddly the actual speed I travel through time is constant and unchanging and this is not just relative to me it applies to everything even photons which will eventually evaporate we all are allotted a span of time separate form general space-time does this then not imply it is a separate force altogether this is what I am trying to get at


(p/s thanks hhEb09'1)

There is no need to think like that, because we can't do it and it's not necessairy to do it or to even think about it.

I understand the analogy is bad as it would never reach the speed of light, but we can speed it up enough to make a measurable change in the time difference between each timer, we do the same with atomic clocks already and gps would not work with out it.

So it is valid, ok maybe I get hung up on the speed of light as a term which I did not need to use

So then if we add a second pendulum but moving away from the first stationary pendulum as fast as physics allows the object to move, then not only do we change the space between each object we also change the position of each object in the general flow of space time relative to each other, what I am saying we can manipulate one part of space-time, the space aspect both in physical distance and distance in the flow of space-time but the unit of time measured by each object remains the same as in the speed of light which is the speed which everything travels through time .

So the fact the unit of time measured is always the same must mean is it a force that is uniform as in it effect all things of all sizes in the same way , and if space-time is classed a one thing then must it not govern even the quantum world ? That is why I cant get rid of the thought of another force of pure time that we are all attached to at a quantum level.

@Ken G
my head hurts trying to grasp all of what your saying it I get the general gist of it might take me a few days but I am sure I will have question about it

Observations are not illusions. Particles moving at relativistic speeds will literally decay slower than twin particles in a lab. If a twin of yours with the exact same heart rate as you have boarded a space craft and sat still while moving at relativistic speed with you remained put, his/her heart rate would change by your measurement from what you measured before he/she left. The traveling twin, taking her own heart rate, would not notice any change at all. There are two reference frames here, two distinct coordinate systems whose displacements through space and time individually differ, but whose displacements through space-time do not differ.

Time is relative but space-time is not. You travel through space-time at speed c. You do not travel through space at speed c nor do you travel through time at speed c. Photons do not travel through time. All of their energy is displaced through space.

Yet, what I just said applies to special relativity discussions for the most part. People are often inquiring about the cosmic speedometer and how fast things go.

But what does the whole universe move with respect to? It cannot move with respect to anything else. If it did, then that anything else would be a part of the universe. Therefore, special relativity breaks down on the universal scale and we do have a special frame of reference. That is where general relatvity must take over. Gravity is space-time and gravitational waves are made out of space-time and black holes are the saturation of space-time. If you wish to observe an example of space-time structure, you can. Just watch rain drops falling from a roof top, one following another, and notice how they separate with time as they fall. The rate of their separation is 9.8 m/sec^2. Two rocks rolled off that same roof, one after the other, will get the same result.

I would discard your examples of pendulums moving beck and forth relative to one another. Pendulums cannot move away from one another at speed c. Their pivots are not moving relative to one another at all. The pendulum's arm moves relative to its pivot and the more distant a point on the pendulum is from the pivot, the faster and further it travels through space relative to the pivot, but not time. Swinging pendulums are often subjects of discussion in relativistic circles when trying to describe different forms of reference frames.

Further, be careful when thinking about dimensions. We have three dimensions that constitute volume and we have a finite amount of charges and charge carriers along with a topological structure that allows for it.

Hi there

I think you need to consider the point of view put forward by Einstien, regarding the way that space and time works to an observer who is "on the outside looking in". If you put yourself in that position, it should become clearer to you.

Regards

Also think about what happens when something travels at the speed of light (As yet proven to be physically impossible for something with rest mass). If you were able to achieve light speed, according to theory, observed in your frame of reference time would be dilated to zero and space would be contracted to zero. This is why the speed of light is a limit. There's no point in trying to achieve greater speed because it can't exist for the traveling you.
I do agree though that space-time is the governing factor rather than C. Space time shrinks to zero for anything traveling at C, or we could say that space-time expands for anything traveling slower than C. Where i get confused is if everything is relative then how does space-time know who is doing the traveling?

@blueshift
I thought and correct me if am wrong that the particles rate of decay is identical only their position in space time relative to each other has changed so an observer at a static point in space-time will be under the illusion one particle has decayed slower than the other when all we have done is alter the positions in a flow of space-time by inputting energy into one particle but the speed through time of each particle has not altered meaning speed c?.

Here is where I have a problem and my questions begin I agree time is relative but not space-time, but the statement I travel through space-time at speed c. sounds like a contradiction of the first statement “Time is relative but space-time is not. “ I can see how I travel through time at speed c. a constant fixed rate but the rate at which I travel through space-time can be altered in relation to other objects which means my speed through space-time is not fixed.

@roger
I am trying but it is a lot to get my head round.

@cosmocrazy
I get confused by lots of things but i do agree your right on why the limits exist

Why is it an illusion? We can synchronize two atomic clocks, leave one on the ground and put the other on a jet-plane and fly it around the world and when the plane returns the clocks are not synchronized anymore. One atomic clock has ticked differently to another, due to time-dilation (this has been done). The difference in the elapsed times on the clocks when they are both back in the same place is no illusion.

If you put your identical twin on a spaceship and send him off on a journey at relativistic speeds, when he returns he will be younger than you. Whatever speed you are moving at, c is always around 300,000 km/h faster than you.

Maybe I am not explaining it clearly enough what i am trying to say but the difference is not the illusion it is a fact of time dilation between two objects, the illusion is that we made the clock run slower, As I understand it we have not made anything run slower we have just changed it's position in space-time relative to the other clock and if both clocks had observers tied to each they would have measured both clocks always ticked to the same decay rate just not relative to each other in space-time so the clock never slowed down (the speed it travelled through time at, speed c)

There is no contradiction. I'll put it mathematically for you. Do you understand Pythagoras? Given a right triangle with the hypotenuse = c, base = a height = b and "^2" to mean "raised to the second power" then:

a^2 + b^2 = c^2. Both a and b are components of hypotenuse c.
Now do the same to space-time but I will include a mistake only for a temporary illustration:

space^2 + time^2 = space-time^2. Both space and time are components of space-time.

The mistake I made deals with the fact that I failed to include the momentum through each of the 3 spatial dimensions and to further place an important minus sign in front of time^2. That is important to keep the speed of light constant to all inertial reference frames.

You cannot travel through time at speed c unless you fail to displace through space. Even sitting in front of your monitor you have displacement through space in the reference frame of the earth.

You need to understand that there are clocks, many of them all over a reference frame. All of those clocks make up the "observer".They do not move with respect to one another and information from one clock to another does not arrive instantly at another clock.

You further need to study simultaneous events. Without doing that the study of time will not make much sense. What is simulataneous to observers in one frame of reference is not simultaneous in another frame of reference unless the two events take place at the same location.

Mostly, relativity is new to you and you are doing the same thing we all did when starting. You are jumping to many false conclusions and need to really slow things down.

http://www.black-holes.org/numrel1.html

I note that Brian Cox mentioned the 'travelling through time at c' concept on BBC Horizon a week or two ago. Some version of this concept seems to be mainstream (or fairly mainstream) physics.

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@eburacum45
yeah great show and got me thinking

@blueshift
Well again i been have told again after checking we do travel through time at speed c but not space-time,

That does not relate to travel through space-time any travel we undertake within the universe is actually only in a straightline between two points in space-time in a foward motion we can alter the speed we travel between each point but the actual time relative to each object is fixed and we cannot alter the speed at which an object travels through time but we can alter it's speed through space-time giving rise to time-dialation between two objects relative to each other in space time, so again saying one clock has slowed down is wrong.



Momentum in 3 spaitial diemnsions does not really make sense and 3d only really states the axis of volume and as space-time is a requirement for any movement you can not move without it, yes you can plot a graph but only because you expeirence space-time can you do so, meaning it is always woven into the graph though we may have trouble understanding it is.

Take a man crossing the road he is actually about to travel in space-time and what’s more he can calculate his present start position and the future end position he can also track and plot the current and future location of cars on the road constantly, he also is constantly able to correctly alter and calculate his speed relative to other objects and we do this without really thinking about it maybe even while talking on the phone.

Movement or the Momentum of volume without space is impossible.
Movement or the Momentum of volume with space and without time is impossible.

relative time does not = space-time so I am not displacing anything.

It does. You have an X-axis, a y-axis and a z-axis for a coordinate system of 3 dimensions. Or, to make it familiar to you, one can travel along the east-west axis, the north-south axis or the up-down (some prefer to use the term "inward-outward" instead) axis or a combination of all three. Momentum can be measured for all three and it can come to zero for any one or all three if you just remain put and do not move with respect to earth. But you are still displaced through time when you sit still. You do not stop aging and neither does rock lying on the ground. when time is the dimension that your energy is most displaced, then time has a positive sign and all the three spatial dimensions have a minus sign in front.No it is along a geodesic. No. The proper time is fixed, the coordinate time is not. If all of time were fixed then muons in a lab would decay no slower than those created by cosmic ray collisions with the earth's atmosphere which should never make it to earth's surface. Yet, they do and their decay rate, their time is different. If time dilation was not valid, old CRT TVs would not be focused.You cannot alter its proper timeNope. Sorry, the universe is a special frame of reference. You still fail to understand Einstein's hypotenuse.You need to study Einstein's clock towers and how they function.So you are telling me that you cannot travel northeast and uphill or downhill at the same time? That is momentum in 3 spatial dimensions.All axes are axes of volume in three dimensions.Don't you really mean that I cannot move without going through it? You seem to be implying that I am taking space-time with me. That does not happen. space-time is not at rest with respect to me. Only my reference frame is. Is English your native tongue? It doesn't sound like it.That is not an example of relativity. Instead, put a float in a homecoming parade going down the street. Two people are playing catch with a photon while riding on the float and the photon's path is at a right angle to the motion of the float. The photon moves at speed c.

You are standing along the road and measure the displacement of the photon differently than the two playing catch do on the float. They simply see the photon moving straight forward and backward. Their coordinate system is the float, sharing their motion. Your coordinate system is on the ground, where you share its motion. You don't measure the displacement of the photon going in any straight back and forth travel as they do. You measure the photon to take a zig-zag path. Those zig-zags are hypotenuses of right triangles while they just have heights to triangles. The photon travels at speed c to you and it travels at speed c to them. But the very same photon takes a longer journey in your frame of reference than it does in their. Since time is equal to space divided by speed and speed is the same for both, then time and space is changed for each. Yet, it is the same photon.Momentum of the volume of what? If you mean "mass" then you are right. If you mean light then you are wrong. Photons do not age. They do not travel through time. The stars above your head are the proof. We are seeing them as they were many years ago. The photons that left your body in some old photo you have of yourself as an infant are still traveling and spreading outward at speed c. The image of your face has weakened and obey the inverse square law just as the distant stars do to you. But they are still there are they are bring the message of your birth to some civilization billions of light-years away.Why are you trying to take on relativity? There are more experiments that vailidate it than there are nails pounded into wood by carpenters in the history of the human race. Only quantum physics has more vailidation. Go to www.teach12.com and take up a video course in science for non-scientists. Then pick up a physics textbook and start working out some problems. After that..?

@ blueshift ;
I think you are being a bit hard....
So some of the detail does fly against mainstream views... I find tolerance and understanding important. Careful explanation and guidance are what Alexander is asking for. His post thus far has not been unreasonably constructed. Questions worth asking. Understanding comes to some of you easy. Its only from challenging the mainstream view that understanding is gained. My advise would be to walk quietly, look and listen. Understanding will come with knowledge.

could a Mod or Admin adjust Alexander´s "posts-counter" please?

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1 + e^i*pi = 0

Don't we travel through time at a speed of one?

Someone beat me to it.

Thanks for the input astromark. I likely came across that way but without any verbal exchange and looking at one another's facial expressions, body language, etc., it can be difficult to read someone's intention at times. Sometimes I need to remember that the more I explain something, the worse things can get.

It always says Posts: 13 . The count doesn´t change!

__________________
If everyone had even a basic grasp of scientific principles, this planet would be a better place (Phil Plait)

Die Lücke, die wir hinterlassen, ersetzt uns vollkommen [The gap we will leave behind will take our place entirely] (Carl Heinz Schroth)

1 + e^i*pi = 0

My $0.02
Can one even travel faster than light? light may be the one thing known to reach the absolute observable limit of speed while at the same time being the defining factor in the absolute limit on observed speed. In traveling faster than light, would you in fact arrive before you actualy arrive, as someone at your point of arrival or point of departure would observe, or rather not be able to observe?

A point i made earlier is, once you've reached the speed of light in your reference frame, time and space would be zero. The instant you reached C your journey would be over regardless how far your destination was. Once you reach C there is no space to travel in.

@Blueshift
Einstein says the reason that time dilation occurs is because when we travel fast in space-time we use some of our energy up at speed through time, but you could also state the effect was caused by a separate force of time existed uniform and relative to all objects within space-time no mater what their postions are in a space-time event relative to each other.

You do not move up, down or backward or forward , as Einstein states the only motion allowed is forward in time or space-time, and space-time has only 2 axis space and time and both run parallel to each other in the same direction , so therefore all motion is in a straight-line in a forward direction it also means only forward forces can be exerted in space-time and as our speed through time is a constant fixed rate speed c, then how can energy in at space-time equal a reduction in speed through time for any object relative to another as the only change it can make is in a forward motion a reduction would require a force with motion in the opposite direction so saying an object can somehow reduce it’s speed through time relative to other objects sounds very much like appling a force in a direction other than forward.


How i see it Lets take space-time as the usually rubber band analogy but this time stretch it across a river and emerge it in the flow of water no matter how you move objects in relation to each other along the expanding rubber band they all feel the flow of the river at the exact same rate no matter what they do on the rubber band they can speed up their movement on the rubber in relation to other objects in a forward motion and experience positions on the rubber band further along than other objects in relation to it, but to the river all objects on the band are just stationary and the reason we can’t change the speed at which we travel through time is we can only ever travel in a forward motion in the expansion of space-time and that is irrelevant to the flow of time it is not a statement of thoery just a disagrement on why a certain effect has happened.

no that is just an abstract concept we use to plot locations in reality all we do is move objects in a straight line between two points in a forward motion within the space-time expansion event which we all call the big bang.

Secondly how do I travel in only one axis unless it is time? How do I travel west if west is just an axis without adding a space-time event to move along? The 3 axis are properties of the volume and space-time just expands along those axis, the only reason you can travel anywhere is space-time creates the place you want to get to and it wont exist without it, a coordinate system has axis 3 of volume and can only state a point within it which is an abstract view of an objects relative position in space-time as time never stops when objects positions are plotted as points in 3 axis,it only states something moved through that position relative to axis of coordinates It’s motion is always in only one direction in a straight line through no mater how many points you would plot, but oddly space-time is always part of the plot and coordinates as luckily space-time is or are automatic, space-time is motion and a requirement for all things contained within the space-time expansion event we just take it for granted and the reason the coordinate system makes sense is that it also travels through space-time.

Not at all space-time is an event that is expanding within the universe we are in this event and move along it’s expansion in a forward motion we can however change our position in expansion relative to other objects by means of exerting energy in to equal distance travelled along it’s expansion which must mean general space-time and my local time are disconnected or changed in some fashion relative to each other so if they are relative to each other then they must be two distinct entities, so it would require a separate one dimensional force of time that does not change to regulate my speed through time as i change my position in the expansion event another force of time to keep my speed through time at speed c.

I know the rate of time is only relative to the observer but how can it be if you say it is a fixed constant relative to each object no matter what their position in space-time relative to each other.

It was 13 when I last replied, and they had 13 posts in the database. Now, they have two more posts, and the counter says 15. Was it saying 13 when they had fewer than 13 posts?
This comment is addressed to @Blueshift, but it taken together with the following comment earlier in the thread leads me to believe that this thread is more likely ATM material, because I am not sure what to make of the phrase "separate force of time". I have moved it again, from Q&A to ATM.

Not true, if A observer's time is "curved" , meaning, compare with a "background / other B observer's " , d^2 (ta)/ (d tb)^2 = (some value).

Under gravitation, time axis bends ... against a background, time "flows".
In it's simplest form, to say it reversely, no matter, time does not "flow".

The "rate of flow" depends on the "Energy".

Forces deal with pushes and pulls. The weak force does relate to time as a time keeper. You might be implying that another dimension of time exists. If it does then you need to demonstrate how one can age in one time dimension without aging in another.Space is not the same thing as space-time. Space is a component of space-time just as electric fields and magnetic fields are components of electromagnetic radiation. When a light bulb flashes, the light moves in all three spatial dimensions at once. After one second its first wave crests are 180,000 miles from the bulb in all directions.

Time dilation occurs because light travels the same speed to all observers and because light speed is not relative. All other motions measure speeds that are relative to one another but not to light. A train moving by you as you stand and watch might be moving 7 miles per hour relative to you. A passenger that walks to the front of the train at the speed of 2 miles per hour will go approximately 9 miles/hr relative to you.

Light does not work that way. A light emitted from a distant train coming toward another train travels as speed c but so does light emitted from trains moving away from each other.If they run parallel to one another, then they cannot be describing the same object.
Are you telling me that I cannnot age unless I move? There are a lot of couch potatoes that will take issue with you. Forward in time has nothing to do with forward in space. You need two reference frames to describe relativity and those two reference frames do not share the same motion or they are not separate reference frames.

There would be no auto crashes from the side, only head-on collisions.No, that is a rubber sheet anaology and does not deal with flat space-time as special relativity experiments do. It deals with general relativity experiments and curved space-time.You better study elastics and forces that are striking an object at differing angles. The rubber sheet would have to be fastened to the shore line one each side with a certain amount of force and the material it is made out of has a certain amount of Young modulus associated with it. It also has sheer modulus and bulk modulus in this situation.If that were true the band would not stretch and the water would not be abel to pass the band. A dam would result.
By sitting right where you are without moving.Events are occcuring whether or not you move through space. Secondly, one cannot move westward unless westward is some part of some coordinate system that also has eastward, northward/southward and describes some elevation changes. Volume is a part of space-time. Volume is space. There are no special frames of reference and no special motions that all other object use as the sole benchmark except for light speed.

Produce an experiment and publish the results to a peer-reviewed journal and file a patent for some invention that backs it up. It is required that you back up your statements here.