Thank you for adding other references to mine on critics of Barbour's approach. You should read Smolin's book The Singular Universe], you might enjoy it.
I am reading Lee Smolin's book.
As far as pragmatic scientists are concerned time is what you measure with a 'regular clock' because that is how you define it.
It is circular. The clock measures movement which takes time and it is used to measure time.
A universal definition of time without circularity, is elusive.
From the wiki on time here]
Time has long been a major subject of study in religion, philosophy, and science, but defining it in a manner applicable to all fields without circularity has consistently eluded scholars.
Bold added by me.
Wrt St. Augustine:
In Book 11 of his Confessions, St. Augustine of Hippo ruminates on the nature of time, asking, "What then is time? If no one asks me, I know: if I wish to explain it to one that asketh, I know not." He begins to define time by what it is not rather than what it is, an approach similar to that taken in other negative definitions. However, Augustine ends up calling time a “distention" of the mind (Confessions 11.26) by which we simultaneously grasp the past in memory, the present by attention, and the future by expectation.
Bold added by me.
Wrt to infinite and finite time:
In contrast to ancient Greek philosophers who believed that the universe had an infinite past with no beginning, medieval philosophers and theologians developed the concept of the universe having a finite past with a beginning. This view is shared by Abrahamic faiths as they believe time started by creation, therefore the only thing being infinite is God and everything else, including time, is finite.
Bold added by me.
If the universe is infinite in space and time, then there is no vested interest to invoke God at all.
Yes kkwan,
In science all measurements are ‘circular’ in the sense that you have to define a ‘standard’ - of Mass (M), Length (L) and Time (T) and then measure everything else by those standards.
If you define the speed of light as constant as measured by observers in all inertial frames then Special Relativity follows and a length can be derived from l = ct, and as E = mc^2 mass can be derived from m = E/c^2 where E = hf, h is Planck’s constant and f is frequency, the inverse of time.
Thus it is possible to reduce all standard base units (M, L, T) to just ‘time’ T with the assumptions that the speed of light c, and Planck’s constant h, are invariant.
All you need is a clock!
In my post #13 I showed how you could define two clocks, ‘atomic’ and ‘photonic’, and using the latter regain an infinitely old universe with no ‘beginning’ in standard Big bang cosmology.
From the prominence of Planck’s constant in my reduction of base units above we might take a hint that the most ‘absolute’ units are perhaps given by Planck units], defined from the Heisenberg Uncertainty Principle.
Of course the universe could be eternal, and most theorists assume it is, with an infinite number of cyclical iterations of the universe before this one, or an infinite process of Eternal Inflation, just as Einstein assumed it was eternal in 1915 and the years following. This led him to reject an expanding solution of his cosmological solution (introducing the Cosmological Constant to allow a static solution) until Hubble’s observations, interpreted by Monseigneur Georges Lemaître, showed otherwise, the universe was observed to be expanding from some sort of Big Bang.
Classically, of course, ‘God’ was conceived of as ‘eternal’ (see St Augustine’s Confessions 4th Cent), so although in an eternal universe there would be “no vested interest to invoke God at all”, there would be no conflict either between such a concept and scientific thought.
In science all measurements are 'circular' in the sense that you have to define a 'standard' - of Mass (M), Length (L) and Time (T) and then measure everything else by those standards.
Ockham, kkwan has shown in the past that he has problems to understand that definitions and measurements can be circular, and that that is no problem at all: see here ]and here].
Maybe you can shine some light on this, as astrophysicist?
Well, once the nature of measurement is pointed out to somebody, and then thought about by them, there is not much else one can say to shed more light on it.
The need to find ‘absolute’ definitions and measurements - particularly about a subject such as time - can at times seem almost to be a religious need, like the need to have an ‘absolute’ god.
kkwan - think about a dictionary - each definition of a word may seem to be definitive, however it defines the meaning of a word by the meaning of other words and if you look up those other words then you can easily end up with the word you ‘first thought of’.
The definition of words would therefore seem to be circular, however what is important is the relationships between words, it is this network of the relationships between words that give language meaning and its power to communicate, words have an operational definition. It is the same with scientific and especially physical concepts.
Looking at the two threads Gdb referred to I will make a comment, but you must understand and accept that I am speaking as a scientist, a relativist (as in SR & GR), and not as a philosopher, religious believer, or whatever.
As a physicist we do define concepts ultimately by how we can measure them, we have no other way, they are operational definitions, it is how they relate to each other that’s the trick.
Although this, together with restricting its knowledge to what can be observed, tested and hopefully falsifiable, might seem a limitation of science, it has been its greatest strength and power.
Now space, time and gravitation are inextricably linked in General Relativity, and GR has been “observed, tested and not yet falsified” to the greatest degree in Solar System experiments.
Physicists have to measure time with clocks. You can measure time by the experience of time passing, memories of time past etc. but these subjective measures are inconsistent.
However GR treats time as a dimension, together with the three space dimensions, and under the “observed, tested and not yet falsified” assumption of the invariance of the speed of light in all inertial frames, clocks can be used to measure distances as well (radar).
The hypothesis that mass causes a curvature of space-time determined by the Einstein Field Equation Einstein field equations - Wikipedia , which explains gravity, has been tested within the Solar System and forms the basis of our best understanding yet of the relationships between those concepts. It is not sacrosanct, it is not the last word - only our best so far.
There must be a deeper understanding, one that includes quantum mechanics as well, and finding such a quantum gravity theory is one major quest of research today.
There may be no ‘final word’, no absolute explanation - it may be ‘Turtles all the way down’ Turtles all the way down - Wikipedia .
That’s the beauty of science, it is not in the ‘kill’, it’s in the ‘chase’.
Thanks Ockham, that was pretty clear. I also have used the example of the dictionary to explain why definitions necessarily must be circular. But some absolutist thinking people simply do not accept this simple fact.
Yes kkwan,
In science all measurements are 'circular' in the sense that you have to define a 'standard' - of Mass (M), Length (L) and Time (T) and then measure everything else by those standards.
If you define the speed of light as constant as measured by observers in all inertial frames then Special Relativity follows and a length can be derived from l = ct, and as E = mc^2 mass can be derived from m = E/c^2 where E = hf, h is Planck's constant and f is frequency, the inverse of time.
Thus it is possible to reduce all standard base units (M, L, T) to just 'time' T with the assumptions that the speed of light c, and Planck's constant h, are invariant.
All you need is a clock!
Sorry for the delay in replying to your post. I have just recovered from food poisoning in the last few days.
Did you not noticed that all these standards involve time?
So, it is crucial to define and "measure" time without circularity as the clock does not.
From the wiki on circular definition here]
A circular definition is one that uses the term(s) being defined as a part of the definition or assumes a prior understanding of the term being defined. Either the audience must already know the meaning of the key term(s), or the definition is deficient in including the term(s) to be defined in the definition itself. Such definitions lead to a need for additional information that motivated someone to look at the definition in the first place and, thus, violate the principle of providing new or useful information.
kkwan - think about a dictionary - each definition of a word may seem to be definitive, however it defines the meaning of a word by the meaning of other words and if you look up those other words then you can easily end up with the word you 'first thought of'.
The definition of words would therefore seem to be circular, however what is important is the relationships between words, it is this network of the relationships between words that give language meaning and its power to communicate, words have an operational definition. It is the same with scientific and especially physical concepts.
Not quite so. False analogy.
From the wiki on circular definition here]
Dictionaries are sometimes used erroneously as sources for examples of circular definition. Dictionary production, as a project in lexicography, should not be confused with a mathematical or logical activity, where giving a definition for a word is similar to providing an explanans for an explanandum in a context where practitioners are expected to use a deductive system. While, from a linguistic prescriptivist perspective, any dictionary might be believed to dictate correct usage, linguists recognize that looking up words in dictionaries is not itself a rule-following practice independent of the give-and-take of using words in context. Thus, the example of a definition of oak given above (something that has catkins and grows from acorns) is not completely useless, even if "acorn" and "catkin" are defined in terms of "oak", in that it supplies additional concepts (e.g., the concept of catkin) in the definition. While a dictionary might produce a "circle" among the terms, "oak", "catkin", and "acorn", each of these is used in contexts (e.g., those related to plants, trees, flowers, and seeds) that generate ever-branching networks of usages.
Bold added by me.
Looking at the two threads Gdb referred to I will make a comment, but you must understand and accept that I am speaking as a scientist, a relativist (as in SR & GR), and not as a philosopher, religious believer, or whatever.
As a scientist, are you not concerned and curious like Lee Smolin and some scientists are, wrt what time is if time is such a fundamental entity in the universe?
Thanks Ockham, that was pretty clear. I also have used the example of the dictionary to explain why definitions necessarily must be circular. But some absolutist thinking people simply do not accept this simple fact.
GdB, it is not as simple as you put it.
And BTW, the example of the dictionary is erroneous.
Defining gravity, space and time circularly implies we don't know what they are.
That is hardly scientific at all.
Thanks Ockham, that was pretty clear. I also have used the example of the dictionary to explain why definitions necessarily must be circular. But some absolutist thinking people simply do not accept this simple fact.
GdB, it is not as simple as you put it.
And BTW, the example of the dictionary is erroneous.
Defining gravity, space and time circularly implies we don't know what they are.
That is hardly scientific at all.
The dictionary analogy was quite accurate actually. In the end of the day we are communicating something: a human experience.
If the definition is that of an 'oak tree' then ultimately you point to an oak tree and say "That is what I am talking about", its a little more difficult with abstract ideas, but there the significant fact is how such ideas relate to each other, as with mathematical ideas.
In astronomy and gravitational physics definitions revolve around that which is observed, measured and tested by experiment, and with time that necessarily involves clocks.
We do know what time is as a physicist when we measure duration with a clock, just as we know what space is when we measure it with a ruler of some kind.
Such knowledge and definition is operational and it is powerful in understanding and controlling the physical world.
If you are looking for an ultimate explanation then perhaps you are looking for 'god'.
I am already at page 100, and still waiting on some real content. If it was not (partially) written by Lee Smolin, I would have put aside as some other crackpot theory: too much speculative talk about the 'error in the Newtonian paradigm' and why physics are on the wrong path with present day cosmology.
Ockham, thanks so much for your thoughtful answers, reminds me of just how much I’ve forgotten since the days when physics was a part of my life I probably should have started the thread in the Psychology wing. I was thinking about real scientists who study the big stuff and what motivates them to look for a single answer. Like you said, history has shown simplification has certainly had a great track record. I was speculating that the reason they do is because of culture. If things had gone a different way, and Hinduism with its menagerie of gods was dominant in the west, I wonder if scientists would think differently.
I have a background in programming so I always consider things as if it was a software question. Imagine we found this computer thing that prints stuff. And we wanted to know what makes it tick. Asking what’s the single programming language that ties its operations all together would be a mistake: the printing part is handled by Postscript/Lisp and the operating system is handled by, let’s say C++. My original question was, why couldn’t the universe be similar…maybe it’s just the fact that there are two mechanisms the run the whole show…gravity and the electroweakstrongthingy (sorry can’t recall what it is). And that’s just how it is.
And btw…I didn’t mean to imply that science/scientists are like religionist/priests just because there might be this relationship in mono-thinking.
Thank you for your kind comments CuthbertJ.
An interesting corollary of the ‘simplification’ thing is that of the methodology of reductionism.
So by breaking down complex systems, such as biological ones, we have been able to understand how things work and the basic principles that underlie the phenomena studied, such as the DNA molecule that is common to all living systems no matter how diverse organisms are from each other. This methodology might be seen as a result of thought processes that seek a unity, and such thought processes might be seen to be inherent in a monotheistic culture .
However we are also becoming aware of the importance of the holistic picture - how a system works in its entirety and that it is more than simply the ‘sum of its parts’. Such a holistic point of view might be seen more as a product of an Asian culture.
Interestingly the Hebrew view was holistic in nature and as far as I know reductionism as a methodology was more a product of Greek thought.
:-) Great statements that make the point, Handydan!
O come on, on the contrary - they are BS.
"Physicists have a common desire to discover the theory of everything. Many are convinced that there is one very elegant equation that will encompass everything. It is more an ego thing really. They want to be the last greatest scientist who figured it all out. They want to be at least as well known as Albert Einstein. It seems to me that they have a tendancy to search for the answers they want to believe are there and ignore things that are not moving their work in the direction they want to go. I think that this approach is rather unscientific and prone to obvious biases. But, I don’t think it is a religious devotion. Religions start with all the answers. Science starts with the questions. "
First of all the mark of a great scientist is humility - humility in the face of the 'universe out there'. A humility that counts their own ideas worthless in the face of demonstrable falsification.
Often a unifying principle behind complex phenomena has in fact been discovered and confirmed by observed predictions, and this has been the history of science, which has been one of ever greater simplification.
The birth of a great theory has often greatly simplified the complexity of the evidence thus far discovered, for example, Newton's gravitation explained countless observations of different phenomena, from the 'falling of an apple', to the orbit of the Moon, to the orbit of the Earth and other planets, to the trajectory of a projectile: an Apollo moon rocket, or a Voyager spacecraft journeying past the gas giant planets to the outer limits of the solar system.
But Newton was not sacrosanct - a tiny anomaly in the orbit of Mercury demonstrated Einstein's General Relativity to be a more accurate theory at describing strong gravitational fields.
Maxwell unified the electrostatic force and the magnetic force, Abdus Salam and Stephen Weinberg unified the strong with the weak nuclear force and electromagnetic force.
The final particle predicted by this theory in the 'standard model' was the Higgs Boson recently discovered in the LHC. Not a matter of searching for answers they want to believe in but discovering what is actually there.
Sure theorists make lots of conjectures - but each one has to conform with known evidence and then predict some more. The trick is to ask the deepest questions.
"But the peers of physicists are other physicists who want the same thing. They are obsessed with simplicity"
Often reviewers are chosen because they want the opposite thing; and as far as simplicity - have you read quantum chromodynamics or general relativity?
Ockham, I had no problem understanding Handydan statement and his idea. And then he followed it up with the statement that “Religions start with all the answers. Science starts with the questions. Which was quite good, I thought. The topic is Hidden god-think in big science?
You also had a lot of good points. But you left out God and how she relates to science. As far as reading Chromodynamics or general relativity, the answer is, no. As a kid, I want to be a thermodynamic engineer, but work and keeping food on the table for the family has always gotten in the way.
Don't thermodynamic engineers generally make a decent living? What are you doing now that pays so much better than a thermodynamic engineer is paid?
LL
Off topic, just answering a question.
LL, yes, you are right. Back when I was contracting for 18/hr, which is like 50/hr today, the thermodynamic engineers were being paid 90/hr back then.
I have not been doing much of anything the last several years except trying to get my health back to the point that I can be productive. Mostly work on projects. Don’t think I could have ever done a lifetime job to retirement except in a field like thermodynamics. I’m retired now, do to age. Was working on research for the wife’s tale, “I took a toke on a joint, now I am worried that my baby will be born deformed." Hopping to take the summer off and collect the evidence of why that tale was formed and why the Christian Movement against Marijuana moved to a major battle issue. I know the answer, just need the back-up material that is older than the computer and internet. I find that most of the younger generation don’t have a clue as to how this really all came about. Been helping the Marijuana Union get up and running. So far this year I have gotten 19 felony arrests drop to a county misdemeanor. About equal to speeding ticket or charges completely dismissed. In California it is not about right or wrong, or the laws, it’s about keeping a paper mill that is designed for revenue income moving. And these are hardworking people who are trying to realize the American dream and follow the laws.
If I collect the evidence I need, then I will pass the research and my experiences of the marijuana movement and industry in California off to someone who could possibly write a book. Just a note, I tried to find the reason for the passing of the olive branch. There is a lot of theories, but I found none of the theories passed the common sense test. And the common sense answer is not in any of the theories being taught today. The same thing is happening today with the deformed babies’ theory. And I would like to fix it.
If physicists come up with a Theory of Everything most of them woud be out of job. They should be careful of what they wish for. I don’t think there are that many jobs for redundant physicists.
Lois
If physicists come up with a Theory of Everything most of them woud be out of job. They should be careful of what they wish for. I don't think there are that many jobs for redundant physicists.
Lois
Actually there are lots of them - financial services in the 'city' constantly rob the science of the best physicists by offering them huge salaries to do economic modelling.
And there is always the defence industry - the physics of stellar cores and the 'Big Bang' is remarkably similar to that of a hydrogen bomb.
No shortage of jobs there then......
If physicists come up with a Theory of Everything most of them woud be out of job. They should be careful of what they wish for. I don't think there are that many jobs for redundant physicists.
Lois
Actually there are lots of them - financial services in the 'city' constantly rob the science of the best physicists by offering them huge salaries to do economic modelling.
And there is always the defence industry - the physics of stellar cores and the 'Big Bang' is remarkably similar to that of a hydrogen bomb.
No shortage of jobs there then......
The jobs are not what most physicists were expecting when they decided to be physicists. Engineering, economics--sidelines.
Lois
I probably should have started the thread in the Psychology wing. I was thinking about real scientists who study the big stuff and what motivates them to look for a single answer. Like you said, history has shown simplification has certainly had a great track record. I was speculating that the reason they do is because of culture. If things had gone a different way, and Hinduism with its menagerie of gods was dominant in the west, I wonder if scientists would think differently.