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Posted
3 hours ago, studiot said:

Does a hole exist?

What is the temperature of a hole?

What colour is a hole?

The thing is, objectivley, a hole is an abstract idea. Even in our language, what we call a hole is not an entity, it is the place where an entity once was. So a hole cannot have temperature or color because it is not an entity in and of itself.

However if you look at it as science, you can say that a hole, unless in vacuum, has the temperature of the air around it, and it's color would be that of the gas in it (Assuming that the hole is on Earth).

Posted
1 hour ago, Acreator said:

The thing is, objectivley, a hole is an abstract idea. Even in our language, what we call a hole is not an entity, it is the place where an entity once was. So a hole cannot have temperature or color because it is not an entity in and of itself.

However if you look at it as science, you can say that a hole, unless in vacuum, has the temperature of the air around it, and it's color would be that of the gas in it (Assuming that the hole is on Earth).

I'd be quite happy to discuss the general philosophy of reality, truth existence material v abstract but that should be done in another (new) thread as it is really off topic here.

So if you wish to discuss further, by all means start a new thread with these quotes, but be prepared for some suprises.

I am fond of saying that Nature is more varied and suprising than Man has ever dreamed.

Posted (edited)
7 hours ago, studiot said:

Rubbish, there are plenty of useful statements that can be made about something non existent.

(1) If it doesn't exist it has exactly zero mass (or does it, wait and see)

(2) Does a hole exist?

(3) What is the temperature of a hole?

(4) What colour is a hole?

(5) What is the value of the centrifugal force due to the Earth's rotation,  in London?

Use your(scientific imagination)

 

"Rubbish, there are plenty of useful statements that can be made about something non existent."

 

I said nothing about "useful". Here's what I said again that you responded to: "Nothing true can be said of a non-existent entity, except perhaps that it doesn't exist."

 

I've numbered your five examples for convenience.

 

The predicates true and false apply only to "assertives", i.e., statements, or as I noted earlier, propositions, to be more precise.

 

For example: "Tokyo is the capital of Canada" is a statement, thus "truth-evaluable" (as they say), and in this particular case we would assign it a value of "false".

 

The predicates true/false do not apply to other speech acts, such as commissives (e.g. "I promise to love you forever") and directives (questions, commands, etc. E.g "Please open the door", "How old are you?"). We say they are not truth-evaluable. They may have conditions of satisfaction (in John Searle's jargon) -- they can be satisfied or not -- but the predicates true/false do not apply.

 

Of the five "statements" you listed, only the first is a statement, thus truth-evaluable. Your (2) - (5) are questions (thus directives), not statements. The question of truth/falsity, therefore, does not arise.

 

So we only need to consider (1). Now, given that "it" doesn't exist, then nothing true can be said of it. This is entirely uncontroversial. What's disputed is whether the (conditional) statement should be assigned a value of false, or neither true nor false. As I noted earlier, depends who you ask. Russell, for example, endorses the former; Strawson, for example, endorses the latter.

8 hours ago, swansont said:

You have chosen an example using things that physically exist, and for which such certainty exists. But this is physics. What if this is applied to things that are somewhat less tangible?

Is a concept part of reality? 

 If the existence of the entity is in doubt (quarks, say, or choose your own example), then we would simply withhold judgement on whether to assign a value of true or false to any statement regarding that entity. We're in the dark, so to speak, at least for the time being.

 

Is a concept part of reality? I'd say so.

8 hours ago, swansont said:

Like this. Unicorns can indeed be sexy, if we are talking about a concept stemming from a mythology. In fact, one could define such a creature as being sexy, since the concept is unfettered by the constraint of having to physically exist.

 This does indeed get tricky. Statements about unicorns, if taken literally, and granting they do not exist, are uniformly assigned a value of false. This much is uncontroversial

For fiction, on the other hand... well, again, depends who you ask. "Sherlock Holmes lives at 221a Baker Street", for example. Some would say true within the context of the fiction; false (or neither true nor false) otherwise. (Did I get his address right?)

8 hours ago, swansont said:

And yet it [Newtonian gravity] is very useful.

Quite so. I know of no one who would deny this. I certainly don't.

8 hours ago, swansont said:

He [Weinberg] is entitled to his opinions.

As are you, swansont.

However, you did claim that science does not tell us about reality ("But if you mean they tell you what reality is, then no. Science doesn't do that.") as if this were a universal position held by all scientists with the implication, "ask any scientist and they'll tell you the same thing".

Clearly this is not the case. Many scientists -- I'd guess the majority -- do believe science can tell us about reality.

 
8 hours ago, swansont said:

If it's truly unobservable then it is not measurable in any way. There's no way to test it. It's not part of science. It lies outside of the scientific methods

 

This gets tricky too. Different people have different notions about what counts as observable/unobservable.

 

Personally, I'd regard quarks, say, as unobservable (you may disagree). Yet science has measured... er, you're the physicist... spin, mass, etc?

6 hours ago, Strange said:

Harry Potter is a boy wizard - True or False?

 See my response to swansont above regarding fiction (Sherlock Holmes).

Edited by Reg Prescott
Posted
1 hour ago, Reg Prescott said:

 If the existence of the entity is in doubt (quarks, say, or choose your own example), then we would simply withhold judgement on whether to assign a value of true or false to any statement regarding that entity. We're in the dark, so to speak, at least for the time being.

Quarks? why would there existence be in doubt?  But you are entitled to your opinion.

Quote

Clearly this is not the case. Many scientists -- I'd guess the majority -- do believe science can tell us about reality.

 
 
The majority? Your opinion again, or do you have a reference for that?
Posted
Just now, Reg Prescott said:

 

A reference for my opinion? Yes, me.

Let me rephrase that...a reputable reference for your claim/opinion

Posted (edited)
12 minutes ago, beecee said:

Let me rephrase that...a reputable reference for your claim/opinion

 

I've no idea.

 

What I would say on the matter, though, is this: From personal experience (in places like this), and from the reading I've done, realism appears to be the default position among scientists. After all, it is the common-sense position, I think you'd agree. Ask a geologist whether or not he thinks tectonic plates are real. Ask a chemist whether or not she thinks molecules are real. And so on, and so forth. I'm pretty sure you'd get a whole lotta "yes"s and precious few "no"s (and no, I don't have statistics; I'm guessing).

 

In other words, if I'm right, we would be told, "Our theories describe, or at least attempt to describe, reality".

 

Now, the glaring exception to this common-sense realist position lies in the realm of quantum physics, where things do get very murky indeed, hence the oft-expressed reticence to make ontological commitments ("Shut up and calculate"). I'm getting the impression that several of our contributors here work in the realm of QM, hence the prevalence of antirealist or non-realist sentiment, and so we may be getting a skewed representation of the overall status of scientists' attitude to scientific claims to knowledge.

 

Hey! Here's a good idea, why don't we just ask them? I'm genuinely curious: Do our members here take a more realist or antirealist approach to their work?

Edited by Reg Prescott
Posted (edited)
20 minutes ago, Reg Prescott said:

 

What I would say on the matter, though, is this: From personal experience (in places like this), and from the reading I've done, realism appears to be the default position among scientists. After all, it is the common-sense position, I think you'd agree. Ask a geologist whether or not he thinks tectonic plates are real. Ask a chemist whether or not she thinks molecules are real. And so on, and so forth. I'm pretty sure you'd get a whole lotta "yes"s and precious few "no"s (and no, I don't have statistics; I'm guessing).

 

In other words, if I'm right, we would be told, "Our theories describe, or at least attempt to describe, reality".

Ahha, so you are coming round...good. Yes theories may attempt to describe reality and or any truth if at all it really exists and if at all it is really knowable. But it is not and never has been a foregone requirement. If theories such as Newtonian gravity and GR give correct results each within their zones of applicability, and if those results coincide [eg: GR gives the same answers as Newtonian albeit with more accuracy] the theories/models are correct. Let's take another example, while accepting that most models are useful approximations that give answers according to our needs, any future QGT will give further answers we surmise, at levels where GR breaks down. That will not mean GR is wrong.  

Edited by beecee
Posted
2 minutes ago, beecee said:

Ahha, so you are coming round...good. Yes theories may attempt to describe reality and or any truth if at all it really exists and if at all it is really knowable. But it is not and never has been a foregone requirement. If theories such as Newtonian gravity and GR give correct results each within their zones of applicability, and if those results coincide [eg: GR gives the same answers as Newtonian albeit with more accuracy] the theories/models are correct. Let's take another example, while accepting that most models are useful approximations that give answers according to our needs, any future QGT will give further answers we surmise at levels where GR breaks down. That will not mean GR is wrong.  

 

Coming round? I haven't taken a stance on the realism-antirealism issue. What I've done is compare what a realist might claim vs an antirealist.

 

You'll find antirealist sentiments prevalent in thinkers such as Mach, Hertz, Duhem, Poincare, Bohr, etc.

 

I'd still guess it's a minority position through scientists across the entire spectrum though. You'll be lucky to find an ornithologist antirealist ("birds don't exist""), for example.

 

And everyone's hero, Einstein, made a celebrated switch from his earlier Mach-inspired antirealist stance to a realist position in later career due his dissastisfaction with the prevailing Copenhagen antirealism.

Posted
22 minutes ago, Reg Prescott said:

Hey! Here's a good idea, why don't we just ask them? I'm genuinely curious: Do our members here take a more realist or antirealist approach to their work?

Well I'm not a scientist, but I'm sure you wont mind me participating. I see space as real [its what separates everything] I see time as real [it stops everything from happening together] I see spacetime as real...it can be warped, twisted, curved, and form ripples in the presence of mass. Quarks etc are even more real and although not seen separately are logically consistent with our models. We cannot observe anything beyond the EH of a BH, but by applying GR and its excellent predictive powers, it tells us that once mass reaches its Schwarzchild limit, further collapse is compulsory, at least up to the quantum/Planck level where the predictive powers of GR fail us.

Posted
11 minutes ago, beecee said:

Ahha, so you are coming round...good. Yes theories may attempt to describe reality and or any truth if at all it really exists and if at all it is really knowable.  

 

Again, you're making a blanket statement. 

 

The realist would wholeheartedly endorse what you just said. The anti-realist, on the other hand, would likely balk.

Posted
Just now, Reg Prescott said:

 

Again, you're making a blanket statement. 

 

The realist would wholeheartedly endorse what you just said. The anti-realist, on the other hand, would likely balk.

Not sure how you interpret that...an agenda again perhaps? I mean I did say "may attempt to describe reality " so how can that be interpreted as a blanket statement.

But hey, again let me remind you that philosophy which is your apparent forte, is what we don't know, while science is what we do know....generally speaking that is. 

And of course sometimes blanket statements certainly do apply.  

Posted (edited)
25 minutes ago, beecee said:

Well I'm not a scientist, but I'm sure you wont mind me participating. I see space as real [its what separates everything] I see time as real [it stops everything from happening together] I see spacetime as real...it can be warped, twisted, curved, and form ripples in the presence of mass. Quarks etc are even more real and although not seen separately are logically consistent with our models. We cannot observe anything beyond the EH of a BH, but by applying GR and its excellent predictive powers, it tells us that once mass reaches its Schwarzchild limit, further collapse is compulsory, at least up to the quantum/Planck level where the predictive powers of GR fail us.

 

Seems to me like a contradictory position. If Einstein's general relativity is taken to be literally true (as opposed to a mere instrument of calculation), then one must claim that space and time as traditionally conceived do not exist. Our traditional concepts of space and time are replaced with a new 4-D spacetime manifold. Out with the old; in with the new.

 

As I said, Einstein himself changed positions on this from an earlier antirealist stance ("GR is not to be taken literally"), to a later realist position ("That's the way things really are").

Edited by Reg Prescott
added "taken to be" and "one must claim that"
Posted
10 minutes ago, Reg Prescott said:

Seems to me like a contradictory position. If Einstein's general relativity is taken to be literally true (as opposed to a mere instrument of calculation), then one must claim that space and time as traditionally conceived do not exist. Our traditional concepts of space and time are replaced with a new 4-D spacetime manifold. Out with the old; in with the new.

You are taking what can only be seen as a weird position. Firstly Einstein's GR gives us a great description of the universe we inhabit: Stop forcing in your "literally true"  Your next faux pax is making a blanket yet untrue statement "then one must" regarding space and time. Space is simply what exists between you and me....and your position and my position at any instant can be calculated with three dimensions. Time is the elapsed period due to the finite, constant speed of light in a vacuum. Einstein, or actually his former teacher Minkowski simply saw the need and observation that a 4D combination of both is more realistic. I'm not sure how you are able to arrive at your conclusion unless for the sake of argument or contrarinness.

Quote

As I said, Einstein himself changed positions on this from an earlier antirealist stance ("GR is not to be taken literally"), to a later realist position ("That's the way things really are").

Einstein did make the occasional mistake and to his credit was big enough to wear such errors of judgement.

Posted
1 hour ago, beecee said:

You are taking what can only be seen as a weird position. Firstly Einstein's GR gives us a great description of the universe we inhabit: Stop forcing in your "literally true"  Your next faux pax is making a blanket yet untrue statement "then one must" regarding space and time. Space is simply what exists between you and me....and your position and my position at any instant can be calculated with three dimensions. Time is the elapsed period due to the finite, constant speed of light in a vacuum. Einstein, or actually his former teacher Minkowski simply saw the need and observation that a 4D combination of both is more realistic. I'm not sure how you are able to arrive at your conclusion unless for the sake of argument or contrarinness.

Einstein did make the occasional mistake and to his credit was big enough to wear such errors of judgement.

 

See in particular the bottom of page 91 and page 92:

https://mechanism.ucsd.edu/~bill/teaching/philsci/fine.realism.pdf

Quote

In particular, following his conversion [from antirealism to realism], Einstein wanted to claim genuine reality for the central theoretical entities of his general theory, the four-dimensional space-time manifold, and associated tensor fields. This is a serious business for if we grant his claim, then not only do space and time cease to be real, but so do virtually all of the usual dynamical qualities.


 

The weird position is your own, I'm afraid. In claiming that space, time, and spacetime are all real (as you did three posts ago), you have one foot in a Newtonian universe and the other in an Einsteinian universe. There is no scientific theory -- that I'm aware of, at least -- which countenances the existence of all three.

Posted

I agree that the scientific method is a lot more fuzzy than the name implies. It sounds like a mathematical formula that you can just roll out, put in the figures, and wait for the answer. But really, it's more an evolved strategy, using the best principles of common sense, and the lessons from the past. So it's an evolving process, rather than a rigid framework. 

The power of statistical results is one example of the evolution of scientific method. 

In the end, the acid test is "does it work?". 

And the answer is generally, "yes it does, better than anything else". For example, the religious method might be likened to Noah and his Arc. Never having built a boat before, Noah solved all of the problems of a gigantic floating structure, when prompted to by God. All straight off the bat. 

Very different to the way that the Jumbo Jet was designed and built. A lot more science went into that. They could, I suppose, have got somebody with no experience or knowledge to build it, and then pray to God that it would fly. I personally prefer the MORE scientific method. Maybe that's what they should call it. It's not pure, it's not finished, but it's the best method we have available.

Posted

Thanks for the input, mistermack. I think much of what you say makes good sense; except, of course, for the use of the term "The Scientific Method" LOL.

 

Does science work? Of course, it does; it works extremely well, in my opinion at least. But two things to say:

 

(1) Scientific theories "working", in the sense that they, in many cases, yield accurate predictions and thus a certain degree of control -- which I certainly don't deny -- is a quite different claim from the claim that (our best) scientific theories are true, or approach truth. I don't discount the possibility, but the latter is a lot harder to argue for than mere instrumental success. There are some pretty powerful arguments, in my opinion, to caution against claims of truth.

 

(2) Science works, we agree. You impute this success to what you call "The Scientific Method", though implicitly you seem to be very close to my own position, i.e., there is no single, timeless, invariant method of science (if it "evolves" -- your word -- then it is neither timeless nor invariant).

 

So how do we we explain the success of science? 

 

First, let me ask, how would you explain the success of the Beatles? Personally, I don't feel they were privy to any unique "Beatles Method"; I think they were just four very talented young lads who came up with one great song after another. Oh, and the occasional stinker too.

 

So why does science succeed where astrology fails miserably? Again, I see no need to appeal to some unique method of science. Perhaps your average scientist is just a bit smarter -- or a lot smarter -- than your average astrologer.

 

Oops, now I've lost all my astrologer friends too :huh:

Posted
1 hour ago, Reg Prescott said:

 

See in particular the bottom of page 91 and page 92:

https://mechanism.ucsd.edu/~bill/teaching/philsci/fine.realism.pdf


 

The weird position is your own, I'm afraid. In claiming that space, time, and spacetime are all real (as you did three posts ago), you have one foot in a Newtonian universe and the other in an Einsteinian universe. There is no scientific theory -- that I'm aware of, at least -- which countenances the existence of all three.

You can deny it as much as you like, and of course ignore the fact that what I'm saying is that theories such as Newtonian and GR while both being approximations, are both correct when applied within their applicable zones and give correct answers. And when you say that spacetime is not real, perhaps you also need to ask yourself the question, are magnetic fields real? If you think a bit and apply your philosophical leanings to that question, you will realise that spacetime is certainly real. https://einstein.stanford.edu/content/relativity/q411.html 

What is a space time continuum?

In 1906, soon after Albert Einstein announced his special theory of relativity, his former college teacher in mathematics, Hermann Minkowski, developed a new scheme for thinking about space and time that emphasized its geometric qualities. In his famous quotation delivered at a public lecture on relativity, he announced that,

"The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. henceforth, space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality."

This new reality was that space and time, as physical constructs, have to be combined into a new mathematical/physical entity called 'space-time', because the equations of relativity show that both the space and time coordinates of any event must get mixed together by the mathematics, in order to accurately describe what we see. Because space consists of 3 dimensions, and time is 1-dimensional, space-time must, therefore, be a 4-dimensional object. It is believed to be a 'continuum' because so far as we know, there are no missing points in space or instants in time, and both can be subdivided without any apparent limit in size or duration. So, physicists now routinely consider our world to be embedded in this 4-dimensional Space-Time continuum, and all events, places, moments in history, actions and so on are described in terms of their location in Space-Time.

Space-time does not evolve, it simply exists. When we examine a particular object from the stand point of its space-time representation, every particle is located along its world-line. This is a spaghetti-like line that stretches from the past to the future showing the spatial location of the particle at every instant in time. This world-line exists as a complete object which may be sliced here and there so that you can see where the particle is located in space at a particular instant. Once you determine the complete world line of a particle from the forces acting upon it, you have 'solved' for its complete history. This world-line does not change with time, but simply exists as a timeless object. Similarly, in general relativity, when you solve equations for the shape of space-time, this shape does not change in time, but exists as a complete timeless object. You can slice it here and there to examine what the geometry of space looks like at a particular instant. Examining consecutive slices in time will let you see whether, for example, the universe is expanding or not.

""""""""""""""""""""""""""""""""""

and this.....https://einstein.stanford.edu/content/relativity/a11332.html 

Can space exist by itself without matter or energy around?

No. Experiments continue to show that there is no 'space' that stands apart from space-time itself...no arena in which matter, energy and gravity operate which is not affected by matter, energy and gravity. General relativity tells us that what we call space is just another feature of the gravitational field of the universe, so space and space-time do not exist apart from the matter and energy that creates the gravitational field. This is not speculation, but sound observation.

""""""""""""""""""""""""""""""""""""

This may also help.....https://www.youtube.com/watch?v=MO0r930Sn_8

 

 

 

Posted (edited)
17 minutes ago, beecee said:

You can deny it as much as you like, and of course ignore the fact that what I'm saying is that theories such as Newtonian and GR while both being approximations, are both correct when applied within their applicable zones and give correct answers. And when you say that spacetime is not real, perhaps you also need to ask yourself the question, are magnetic fields real? If you think a bit and apply your philosophical leanings to that question, you will realise that spacetime is certainly real. 

 

Not what I said! You really must try to stop misrepresenting me, beecee. It's just not cricket.

 

Here's what I said again:

 

"If Einstein's general relativity is taken to be literally true (as opposed to a mere instrument of calculation), then one must claim that space and time as traditionally conceived do not exist. Our traditional concepts of space and time are replaced with a new 4-D spacetime manifold. Out with the old; in with the new."

17 minutes ago, beecee said:

This new reality was that space and time, as physical constructs, have to be combined into a new mathematical/physical entity called 'space-time', because the equations of relativity show that both the space and time coordinates of any event must get mixed together by the mathematics, in order to accurately describe what we see.

 So, on the above account, first there were two entities (space and time); then there was only one (space-time).

You've asserted your belief in the existence of three entities concurrently: space, time and space-time.

Edited by Reg Prescott
added "on the above account"
Posted

Here's another for good measure..... https://www.quora.com/Is-spacetime-a-real-thing-or-just-a-mere-concept

Is spacetime a real "thing" or just a mere concept?

It's a real concept to most people. Space-time is the substance, the location, the ethereal goo that the earth, us, and every other bit of matter travels through every day. However, to understand exactly what space-time is is a little harder. Space-time is the fabric that makes existence what it is. Without space-time, there is no location. How can there be location when there is no measurement, and how can there be measurement when there is no space to measure? Without space-time there would be no time. How can there be time when there is no movement, and how can there be movement when there is nothing to move through, and to measure time from? Basically, space-time is the age old theory of space, the aether, the celestial body, the heavens, that everyone has always known, only it's combined with time, which is also a concept we've always had. This is because time is nothing but a measurement of movement. It's like this. Move your hand one foot in one second. Now, your hand moved a foot in a second, but the same is true in reverse. It also took a second to move a foot. So time is a measurement of how fast an object moves a certain distance. This is why Einstein combined space and time into space-time.

::::::::::::::::::::::::::::::::::::::::::::::

 

 

15 minutes ago, Reg Prescott said:

 

Not what I said! You really must try to stop misrepresenting me, beecee. It's just not cricket.

 

Here's what I said again:

I know what you said, here elsewhere and the other thread and I have not misrepresented you.

Quote

"If Einstein's general relativity is taken to be literally true (as opposed to a mere instrument of calculation), then one must claim that space and time as traditionally conceived do not exist. Our traditional concepts of space and time are replaced with a new 4-D spacetime manifold. Out with the old; in with the new."

Quote

 

 So, on the above account, first there were two entities (space and time); then there was only one (space-time).

You've asserted your belief in the existence of three entities concurrently: space, time and space-time.

 

Yes first there were two entities...then along came GR and for convenience sake the two entities became one. It's not that hard, unless you are purposely being obtuse or contrary..

Posted (edited)
9 minutes ago, beecee said:

Here's another for good measure..... https://www.quora.com/Is-spacetime-a-real-thing-or-just-a-mere-concept

Is spacetime a real "thing" or just a mere concept?

It's a real concept to most people. Space-time is the substance, the location, the ethereal goo that the earth, us, and every other bit of matter travels through every day. However, to understand exactly what space-time is is a little harder. Space-time is the fabric that makes existence what it is. Without space-time, there is no location. How can there be location when there is no measurement, and how can there be measurement when there is no space to measure? Without space-time there would be no time. How can there be time when there is no movement, and how can there be movement when there is nothing to move through, and to measure time from? Basically, space-time is the age old theory of space, the aether, the celestial body, the heavens, that everyone has always known, only it's combined with time, which is also a concept we've always had. This is because time is nothing but a measurement of movement. It's like this. Move your hand one foot in one second. Now, your hand moved a foot in a second, but the same is true in reverse. It also took a second to move a foot. So time is a measurement of how fast an object moves a certain distance. This is why Einstein combined space and time into space-time.

::::::::::::::::::::::::::::::::::::::::::::::

 

Last sentence: "This is why Einstein combined space and time into space-time"

Where there were two entities before, there is now one.

You've been affirming the existence of three distinct entities.

 

9 minutes ago, beecee said:

Yes first there were two entities...then along came GR and for convenience sake the two entities became one. It's not that hard, unless you are purposely being obtuse or contrary..

 

To refresh your memory...

Quote

Well I'm not a scientist, but I'm sure you wont mind me participating. I see space as real [its what separates everything] I see time as real [it stops everything from happening together] I see spacetime as real...it can be warped, twisted, curved, and form ripples in the presence of mass. 

- you

 

You see three entities as real.

Edited by Reg Prescott
Posted (edited)
50 minutes ago, Reg Prescott said:

You see three entities as real.

Yep, certainly as I have explained to you at least twice now. No problems from this end.

Again, space stops everything from being together: Time stops everything from happening together: Pretty basic lay persons definitions but also valid. Oh, and again, if you claim that spacetime is not real, what semblance of reality do you give a magnetic field?

Let me say at this time, that many times people here and elsewhere use the term space when they mean spacetime....It may seem pedantic, and generally it is accepted, but my own personal feelings is as I have discussed here....space meaning the space between me and the TV, and spacetime being the unified multi-dimensional framework within which we locate events and describe the relationships between them in terms of length, breadth and time. Intervals of space and time considered separately are not the same for different observers.

Edited by beecee
Posted

I think what @Reg Prescott is trying to say here @beecee.

Is why do you see space and time as separate from space-time.

or better yet, why do you distinguish space and time from space-time.

as you said

2 hours ago, beecee said:

space meaning the space between me and the TV

but

 

2 hours ago, beecee said:

spacetime being the unified multi-dimensional framework within which we locate events and describe the relationships between them in terms of length, breadth and time.

emphasizing the last part of the space-time definition.

You said that space is the space between you and the TV, and as space is considered to be measured in length, width and loaf, it fits into the framework of space-time, so why bother distinguishing between space and space-time at all when space-time does a better job at describing stuff anyway. 

Correct me if I am wrong @Reg Prescott

Posted (edited)
1 hour ago, Acreator said:

I think what @Reg Prescott is trying to say here @beecee.

Is why do you see space and time as separate from space-time.

or better yet, why do you distinguish space and time from space-time.

as you said

but

 

emphasizing the last part of the space-time definition.

You said that space is the space between you and the TV, and as space is considered to be measured in length, width and loaf, it fits into the framework of space-time, so why bother distinguishing between space and space-time at all when space-time does a better job at describing stuff anyway. 

Correct me if I am wrong @Reg Prescott

To repeat.....Let me say at this time, that many times people here and elsewhere use the term space when they mean spacetime....It may seem pedantic, and generally it is accepted, but my own personal feelings is as I have discussed here....space meaning the space between me and the TV, and spacetime being the unified multi-dimensional framework within which we locate events and describe the relationships between them in terms of length, breadth and time. Intervals of space and time considered separately are not the same for different observers.

 

Quote

 

Is why do you see space and time as separate from space-time.

or better yet, why do you distinguish space and time from space-time.

 

We all treat space and time as separate and different entities when required....all of us. Spacetime, is the union of the two, in which GR operates.

 

 

Edited by beecee
Posted
33 minutes ago, beecee said:

To repeat.....Let me say at this time, that many times people here and elsewhere use the term space when they mean spacetime...

And sometimes the other way round. For example, “expanding spacetime, which is meaningless. 

36 minutes ago, beecee said:

We all treat space and time as separate and different entities when required....all of us. Spacetime, is the union of the two, in which GR operates.

Indeed. In most cases, Newtonian physics is good enough. 

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