Where is the center of the universe?

[ChrisA]

not at all.

the parameters being used are for carbon based lifeforms.

anthropomorphic orientation

This is a very reasonable assumption. Life has to depend on long polimer chains that fold into shapes.

Water is truely unique. It is the only possible compound that is both an acid and a base. Think of it as HOH, not H2O.

Life is going to need polimers that are soluble in water

Life also has to be built with the stuff that is around and abundent. I think this leads to RNA. What happens after RNA is just luck and accidents of history. I think that here on Earth life just RNA, DNA and proteins cam later. So life could be very different from what we have now but still there are constrainets like water and carbon and so on.

 

[josefnspace]

i recall reading about silicon based life forms in high pressure and temperature.
there are other elements that can produce polymer chains.
we've only begun to view beyond our star system.
.

 

[Catastrophe]

Hypothetical types of biochemistry - Wikipedia

en.wikipedia.org

Cat

 

[billslugg]

I like the one based on hydrogen fluoride. Hydrofluoric acid will etch glass. Must be in plastic or wax container. If it gets on you it goes deep into you, can't stop it. You don't feel it at first. It can mess with your heartbeat.

 

[Catastrophe]

Dissolve a Body in Hydrofluoric Acid Like Fictional Drug Dealers

Could you really use hydrofluoric acid to dispose of a corpse, like Walter White on Breaking Bad? The answer is basic chemistry.

www.thoughtco.com

Cat

 

[Unclear Engineer]

To add a bit to Cat's link, remember this Space.com article https://www.space.com/earth-modern-biochemistry-timeline-metabolic-reactions . It explains how some early biological reactions depended on different chemicals than current life on Earth uses.

 

[Rangerer]

I don't seem able to get this point across to most. The Distance travelled (your question) is time. People need to get their heads around the fact that time and distance units are interchangeable. A light year IS a year and a year IS a light year. This is not a debatable point in current science.
The elephant in the room is time. Time. Where do you see a definition of time rather than some vague assertion about arrows? Or clocks.
Given the above, it is clear that the "centre" does not exist anywhere in the here-and-now universe. It has been left behind in the past. The current model is dead and buried (by data from James Webb) and people cling to the idea of flat Euclidian space simply because it is easy to understand and 'consensus'
Our perception of reality in everyday life is untrue. Grabbing facts and shuffling until coherent mathematics makes sense and describes reality with numbers (spacetime) is a correct result. Minkowski (Einstine's teacher) did a good job of a description of relativity. Alive now he would point out that a better understanding of time (as a spatially additional dimension that does not change relativity mathematics) and we could all move forward to new ideas.
Ha ha. Sorry about the rant but I get so frustrated. It is obvious.
Easy to understand:

Think of a balloon being inflated. This is an analogy that has been used for decades. We live on the surface. (this is the universe description by dropping a dimension to 'make things clear'). Our 3D environment is the surface and nowhere else in this description.
The balloon was just a blob before inflation - The Big Bange event.
Inflate the balloon and you get an expanding universe. The Universe is the surface only. The origin is back in time (a distance away) at the centre of the balloon. Conceivably, if you consider the Big Bang as a piece of material-type substance that has been teased out to the skin of the balloon then you could describe the universe centre as 'everywhere'.
This is ok of course but it disguises the reality of a geometric centre that does not exist in the universe 'now'. By doing this 'everywhere' we avoid having to decide what time actually is and our limited perception of it!

Well, I see the balloon analogy as false. The balloon expands from its original edge, the opening, and pressure is exerted directly into the balloon, creating differing currents; if you inflate it from it's center, please specify the universe in which that can happen.
Also ,a balloon is not a blob. It is a specifically defined and measured manufactured object; if you're making a theoretical balloon, how is it theoretically inflated without interacting without forces outside of it? A balloon is not a sphere, it's distorted by its air vent, and is more like a distorted ellipse. Your theoretical sphere is just not plausible in the Newtonian world.
The BB supposedly was a 'singularity' and expanded from a universal center, outwards, everywhere, so to speak. That seems to allow for the 'center' to remain relatively centered. Since we have discovered celestial bodies in the Milky Way that were formed only a few million years after the BB, then logically it follows that we are very near the original center. I can imagine a 'center' for the universe that is millions of light years in radius, and still fulfills the requirements for a center. It follows, that as far as anyone knows, we are closer to the center than just about anyone.

 

[Gibsense]

Well, I see the balloon analogy as false. The balloon expands from its original edge, the opening, and pressure is exerted directly into the balloon, creating differing currents; if you inflate it from it's center, please specify the universe in which that can happen.
Also ,a balloon is not a blob. It is a specifically defined and measured manufactured object; if you're making a theoretical balloon, how is it theoretically inflated without interacting without forces outside of it? A balloon is not a sphere, it's distorted by its air vent, and is more like a distorted ellipse. Your theoretical sphere is just not plausible in the Newtonian world.
The BB supposedly was a 'singularity' and expanded from a universal center, outwards, everywhere, so to speak. That seems to allow for the 'center' to remain relatively centered. Since we have discovered celestial bodies in the Milky Way that were formed only a few million years after the BB, then logically it follows that we are very near the original center. I can imagine a 'center' for the universe that is millions of light years in radius, and still fulfills the requirements for a center. It follows, that as far as anyone knows, we are closer to the center than just about anyone.

The balloon analogy shows that expanding space can separate objects without them travelling through it. What is outside it or inside it is undesignated (ignored/zeroed)

It was illustrated by astronomers to help people understand how the universe works. The surface is the only relevant part and was called a balloon instead of a sphere to help everyone relate to it easily. In no way was the act of blowing up the balloon held to be part of the method of the universe. Having said that it does extend the analogy to Dark Energy.

The 'skin' of the sphere (balloon) is 3D space both in the analogy and in the Hypersphere. It has 1 Dimension ignored/left off to help get the idea across. The only 'validity' for the internal volume of the sphere is to regard it as history but most say it does not exist materially.

Maybe you would have fun considering the ideas of different dimensions. For a point has zero dimensions, a line has one, a plane has two, a cube has 3, a tesseract has 4 and so on. These are spatial dimensions (distance). It is not quite as simple as it appears when you include time. And then give Special Relativity a go. It is worth the effort, you might challenge the establishment and take it forward - you never know!

 

[Unclear Engineer]

When I read stuff like this, it gets me thinking about how time as a dimension might be connected to the problems we have with quantum theory principles such as the duality of matter being both particle and wave, the entanglement concept, and the superposition concept.

What if reality has a finite dimension along the time axis?

There are people thinking about those concepts. I see stories about "time crystals", etc.

For those of you who have read "Flatland" (a book about a 2 dimensional species living on a planar surface encountering a 3 dimensional being being intersecting their surface), the concept of not being able to perceive a dimension probably has some basic understanding.

 

[Gibsense]

When I read stuff like this, it gets me thinking about how time as a dimension might be connected to the problems we have with quantum theory principles such as the duality of matter being both particle and wave, the entanglement concept, and the superposition concept.

Yes, I think that may be right in some way. How time, or the cause of time, is involved.

 

[Classical Motion]

I have no knowledge but I believe they use length, not time for location. At least I would. And a firm center gives that length.

 

[Unclear Engineer]

If there are some things like photons that have some "depth" in the time dimension, it would probably screw-up our sense of causality. Which is what we keep seeing in quantum mechanics.

It is hard for me to think about how that could work, because I tend to think of time as one-directional and instantaneous, with events in the past not changeable. But, if some things like photons can have a "depth" in the time dimension, then over some short period of time, some event that seemed to happen "after" some other event could still affect that other event that seemed to happen before it.

 

[gsteele531]

If the universe started at a point, 13 billion-odd years ago, it would seem impossible for there to be anything at a distance of 45 billion light years in a continuum where light speed is a limit; but that neglects the fact that as an object approaches the speed of light, time slows down. So to that object, in its frame of reference, only 13 billion years has elapsed, while externally, 45 billion years has passed. In effect, it's 13 billion years old owing to its velocity - but to the external frame of reference, it has been moving for a 45 billion year period. But the velocity is always relative; so the spot of the big bang is also moving away from the object at near-light speed. So IT, likewise, has had 13 Billion years elapse in its frame of reference, even though it took 45 billion years for that to happen in a theoretical static frame of reference.

 

[Helio]

If the universe started at a point, 13 billion-odd years ago, it would seem impossible for there to be anything at a distance of 45 billion light years in a continuum where light speed is a limit;

The speed of light is the speed through space. Since space is expanding everywhere, then the more distant regions are moving faster away from us than the closer regions. Most of the observable galaxies are moving faster than c due to their distance.

So how can light reach us from regions faster than light?

Imagine you want to hit the back door of a bus with a snowball. You can throw it at 40 mph but the bus, as it passes by when you throw, is traveling at 60 mph. Can you ever hit the bus?

Normally not, but what if you have a friend traveling at 30 mph following the bus and you throw the snow ball to your friend in the car? That person can then throw the snowball and hit the bus, right?

Imagine the region where space is traveling at the speed of light relative to us. Now imagine a star shining that is just past that. The light from that star will travel soon into the region of space towards us that is not moving faster than light, thus that light will reach us.

 

[Atlan0001]

The speed of light is the speed through space. Since space is expanding everywhere, then the more distant regions are moving faster away from us than the closer regions. Most of the observable galaxies are moving faster than c due to their distance.

So how can light reach us from regions faster than light?

Imagine you want to the back door of a bus with a snowball. You can throw it at 40 mph but the bus, as it passes by when you throw, is traveling at 60 mph. Can you ever hit the bus?

Normally not, but what if you have a friend traveling at 30 mph following the bus and you throw the snow ball to your friend in the car? That person can then throw the snowball and hit the bus, right?

Imagine the region where space is traveling at the speed of light relative to us. Now imagine a star shining that is just past that. The light from that star will travel soon into the region of space towards us that is not moving faster than light, thus that light will reach us.

This is going to be extremely difficult, Helio!

You, whether the seemingly immobile observer or the mobile traveler, sit at exactly the center of the universe between horizons (both ultimately the same Horizon. The scenery is flowing in and out of horizon fore and aft of you, not you. Never moving away from being centered in universe Horizon, you are gaining observable scenery from two directions, front and rear. Your big problem in that gain is that in the gain, it is t=-1, to you frontally, and t=+1 to you from the rear.

In other words, you are advancing into the future to the front, and advancing into the past to the rear. Counterintuitively, light is coming to you from both directions, from both far horizons always equal-distant from you, at exactly the same speed of light . . . no difference whatsoever though one is positive in direction of time's flow, and the other is negative in direction of time's flow!

There are two opposed clock pendulums swinging against each other, MIRROR opposite to one another, and you, and all else of matter and energy, sit at the bottom of the swings (Einstein's and Hawking's (t=0)) where they come closest together, meeting, in passing by and through one the other in their mirror opposite precisionist mirroring.

 

[Gibsense]

I have no knowledge but I believe they use length, not time for location. At least I would. And a firm center gives that length.

Length as a measure, can be seconds or meters. Time can be expressed validly in meters. In cosmology light years and years are used for the massive sizes compared to everyday events.
It regards time as a distance in a spatially 4th dimension and I suppose also regards an everyday distance as a possible time dimension for 'something' orientated differently from ourselves eg an intersecting hypersphere.
To organise our lives of course there is an obvious difference.

 

[Classical Motion]

I was referring to GPS location, not cosmology. I read an article about it, if I can find it I’ll post it here.

Because of our clocks, and because of the concept of spacetime, which will not allow a stable clock, GPS uses length for triangular plot for location. Not time.

That’s all I was trying to point out.

With spacetime, if there is a relative V, then the time is relative too. But not the length.

But he who makes a stable clock will erase spacetime. And it’s long over due.

 

[Gibsense]

The concept that the universe can be thought of as a 3-dimensional surface in a 4-dimensionals "space-time" mathematical space does work mathematically, and that math is the Lorenz equations of Special Relativity Theory. The "time" dimension is the radius from the center of the 4-dimensional sphere to everything definable with x,y,z coordinates in our currently observed universe. So, it is "time" that is expanding the universe in this analogy. (And doing so at the speed of light, because the length dimension is "ct".)

But, that doesn't try to actually explain the physics - it is just the logical mathematical interpretation of the fact that we cannot seem to measure any difference in the apparent speed of light when we know that our velocity has changed, which is what the Michelson-Morley experiment established as a fact.

But, General Relativity Theory tells us that the apparent rate of time passage is not constant throughout the universe. It is slower in the vicinity of large masses.

RE the last paragraph. Although correct the explanation is in the geometry. At the centre of the mass time ticks at the same rate as the universe generally. Away from the centre time is rotated in its direction (compared to the universe radius) and time ticks more slowly. However, the rotation - in the direction of time - points inwards and the shape (of the gravity well) is maintained.

 

[Gibsense]

But he who makes a stable clock will erase spacetime. And it’s long over due.

A stable clock is the increasing age of the universe but 4 dimensions still exist

 

[Classical Motion]

There is only one dimension and it is orthogonal. Length. Length alone has area and area alone has density. Dimension is not a property of space, it's a property of matter. Space is a void of property and substance. There is nothing there to change.

 

[Helio]

Because of our clocks, and because of the concept of spacetime, which will not allow a stable clock, GPS uses length for triangular plot for location. Not time.

IIRC, GPS uses the time of travel for light/radio signals to a given location. But there are variables that they take into consideration. Time dilation per GR says that the GPS satellite clock will run faster since it is in a weaker gravity field; SR, however, requires a time dilation adjustment as well since the fast moving satellite's clock will tick slower. Then there is the speed of light adjustment due to the slower speed through a medium (ie air).

The faster and slower adjustments for Relativity, although they are counter to one another, are not equal, so there is a net adjustment.

The idea that time equates to length is correct but only in terms of the speed of light. The official length of a meter is now based strictly on the speed of light (counting the pulses for a given wavelength, formerly of Cesium).

 

[ZZTOP]

The universe is undeniably vast, and from our perspective, it may seem like Earth is in the middle of everything. But is there a center of the cosmos, and if so, where is it? If the Big Bang started the universe, then where did it all come from, and where is it going?

Where is the center of the universe? : Read more

If the Big Bang were accurate the center of the universe would be at the center of the big void at the center of everything, without a 14-billion-year wide void there was no Big Bang

 

[Macrocompassion]

This is a very common assumption. But BBT has the universe itself (space) expanding. A balloon will expand such that all the marks, if any, on it remain proportionally the same distance ratio with one another.

Thus, we are essentially in the same location we were after, say, the first trillionth of a second, but space has expanded so much that our close neighbors aren't close any more. [Motions through space, of course, alters this somewhat.]

Its not time that flies but that we ourselves that pass through it. Relative velocity does not help here because we have no measure of the speed of time itself and are therefore forced to think in terms of it standing still.

 

[Macrocompassion]

Or, to put it more succinctly, the entire Universe is beyond our capacity to observe, being limited by the speed of light, which places every observer at the centre of their own observable universe. Furthermore, such observable universes may vary according to means of assisted observation, such as telescopes.

Questions regarding the past and future of the Universe are limited by contingent constraints.

Cat

Does the visible edge of the universe disappear at the same rate regardless of which direction one looks? Should this not be the case it is possible to determine the position where it first began.

 

[Macrocompassion]

I don't seem able to get this point across to most. The Distance travelled (your question) is time. People need to get their heads around the fact that time and distance units are interchangeable. A light year IS a year and a year IS a light year. This is not a debatable point in current science.
The elephant in the room is time. Time. Where do you see a definition of time rather than some vague assertion about arrows? Or clocks.
Given the above, it is clear that the "centre" does not exist anywhere in the here-and-now universe. It has been left behind in the past. The current model is dead and buried (by data from James Webb) and people cling to the idea of flat Euclidian space simply because it is easy to understand and 'consensus'
Our perception of reality in everyday life is untrue. Grabbing facts and shuffling until coherent mathematics makes sense and describes reality with numbers (spacetime) is a correct result. Minkowski (Einstine's teacher) did a good job of a description of relativity. Alive now he would point out that a better understanding of time (as a spatially additional dimension that does not change relativity mathematics) and we could all move forward to new ideas.
Ha ha. Sorry about the rant but I get so frustrated. It is obvious.
Easy to understand:

Think of a balloon being inflated. This is an analogy that has been used for decades. We live on the surface. (this is the universe description by dropping a dimension to 'make things clear'). Our 3D environment is the surface and nowhere else in this description.
The balloon was just a blob before inflation - The Big Bange event.
Inflate the balloon and you get an expanding universe. The Universe is the surface only. The origin is back in time (a distance away) at the centre of the balloon. Conceivably, if you consider the Big Bang as a piece of material-type substance that has been teased out to the skin of the balloon then you could describe the universe centre as 'everywhere'.
This is ok of course but it disguises the reality of a geometric centre that does not exist in the universe 'now'. By doing this 'everywhere' we avoid having to decide what time actually is and our limited perception of it!

How are we to know that the rate of expansion of the universe is the same in every direction? This is the usual assumption, but if it is slower in particular directions this would suggest that its center was further from this direction than from places that has a greater speed of change..