Time does not exist. It is an abstract concept invented by humans as part of our effort to rationalise the extraordinary fact of our existence. The past no longer exists, and the future has never existed. You can’t physically travel around time any more than you can physically travel around mathematics or ethics. All that exists is the fleeting instant.
I would not have thought that needed saying. But there you are. I am not however questioning the value of what sounds like a tremendous piece of research – only the BBC’s populist presentation of it.
Specifically, time travel +into the past+ is impossible. You can travel forward through time as fast as you like, given enough energy or a nearby black hole, but once there you could never “return”; that would involve going backwards from your “new” present.
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Time travel into the past contravenes free will. The conditions for free will are that the future must be unknowable, and the past must be unchangeable.
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I find it very interesting that physical law seems to outlaw anything that would contravene free will. Our universe seems to be a place where morals matter. Our actions can’t be undone.
Look up at the stars tonight, and note “The Summer Triangle”, consisting of Vega, Deneb and Altair, a conspicuous, large isosceles triangle of stars almost overhead. Vega, 25 light years away looks brightest to us, but Deneb looks almost as bright. Deneb is 1600 light years away, so we see it as it was 1600 years “ago”.
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The photons that make the journey do not experience those 1600 years at all. In its own reference frame, a photon has only length (which we measure as time; “light years”). Its lifespan is instantly brief. It is a sort of energy connection from the past to us.
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So in an important sense the past does exist. Everything we see is in our past, linked to us via photons.
I totally agree. I’ve long held these beliefs about time.
Incidentally, Craig, some e-mails I sent you recently seem to have been lost in a time-warp. They must be well beyond the orbit of Pluto by now.
Yes, Clark, kind of. If you zipped around at near light speed, you wouldn’t actually travel in through time in any conventional sense: it’s more like your sequence of events slows down relative to other sequences of events at different locations.
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Of course, talking about weird relativistic effects in conventional physical terms involves warping metaphors even more than warping space-time. (Not to mention than if you zipped around at near light speed, you would have many more serious physical problems than having to reset your watch.)
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I’m not sure how seriously to take the wormhole theory. It’s mathematically fascinating, but it seems to rely on a lot of “what-if” bending of assumptions.
Democracy Now! …now:
[Glenn Greenwald will be on]
http://www.democracynow.org/
I have to disagree with Craig about time not existing. The time dimension t is just as “real” as our three dimensions of space d.
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The Apollo astronauts were far enough from Earth for the light-speed signaling delays to be significant. In particular, the radio messages of the moon landing were heard in a different order on the Apollo spacecraft than on Earth. Here’s a nice page that helps to make it clear, complete with reconstructed audio, as heard on the moon.
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http://www.fourmilab.ch/documents/RelativityOfSimultaneity/
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Nextus, I was thinking from the point of view of a photon, actually at light speed, rather than a massive body trying to approach light speed. This thought experiment is what got Einstein started on Relativity.
“I find it very interesting that physical law seems to outlaw anything that would contravene free will.”
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Quite the opposite. Physical laws seem to outlaw free will. Philosophers have been wrestling for with centuries with the problem of making space for the common sense notion free will in deterministic universe. Some have tried to exploit quantum indeterminacy, but it can’t fill the required role. The doctrine of compatibilism suggests that free will is a illusion apparent only to agents with a subjective viewpoint. Morality is not an objective phenomenon, much less that it constrains anything physical – but it is a subjective phenomenon, with its own set of non-physical rules. At least that’s more or less the settled view amongst the vast majority of moral philosophers (theologists tend to disagree).
Nextus, I simply assume that wormhole theory will be ruled out in due course, as it contravenes free will. Common-sense determinism was overturned by counter-intuitive quantum physics, but then determinism couldn’t support free will.
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Morals are the foundation of our universe.
Nextus, of course morals aren’t “objective”. The universe is not divided into “subjects” and “objects”. That was a distinction invented by humans, and then mistaken for reality. This is what the Eastern philosophies have been telling us for centuries.
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We are at the crux of the modern crisis here. The idea that I can advantage “myself” at “someone else’s” expense is an illusion based upon our subject-object model of reality. Actually, we’re all in it together, and we are stuck with that. “Love thy neighbour as thine self” is not merely an impractical exhortation to be good. It’s actually essential advice for avoiding disaster.
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Try “The Self Aware Universe” by Amit Goswami.
“I was thinking from the point of view of a photon, actually at light speed”
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The same principle applies, and that why there is an ultimate limit. A photon doesn’t have an event-line at all, and there is no “time” for it to travel through. Everything is simultaneous or the photon. The notion of slowing something down beyond zero is gibberish. (By analogy, negative speed would still be speed, but in a different direction). So the travel metaphor doesn’t map entirely well onto our notion of time, because there isn’t really a time “dimension” for travel to take place in. The 4D “space-time continuum” is a pedagogical simplification. The notion is still useful to get certain points across, particularly for the average Beeb audience.
This is getting very philosophical. From the perspective of objective science, subjectivity is arises from the limitation of information at a certain physical point. But of course the notion of an single objective ‘God-like’ view of reality is ultimately a convenient theory invented by subjective agents. Truthfully, we only have a phenomenological point-of-view (in which subjectivity is a very ‘real’ phenomenon.
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Of course we have to choose a starting point. If you choose the objectivity of physics, and apply the subjective metaphor of time, then you run into conceptual antinomies (kudos to Kant for spotting that one!). But if you choose the language of phenomenology, then objective physical laws are convenient fictions.
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Craig was highlighting the ultimate incoherence of the time-dimension view according to the objectivity of physics, which can’t handle the travel metaphor. Naturally, we can ‘choose’ whether to subscribe to the doctrine of objectivity or not: that’s one of the benefits of being a subjective agent (from the viewpoint of phenomenology, anyway).
Nextus, you wrote “Physical laws seem to outlaw free will. Philosophers have been wrestling for with centuries with the problem of making space for the common sense notion free will…”
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Such philosophers need to suspend their concept of self, and embrace Universal consciousness. It all falls into place then. None of this is really as complicated as it seems from within the subject/object model.
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The fundamental lesson from quantum physics is not indeterminacy. It is inseparability and complementarity.
Time exists Craig, and in a very real sense, just as distance exists, or volume exists. Our measurement of these things is what does not actually exist and is simply the system by which we make sense of our world. If time does not exist then nothing exists. The measurement scale we use for time, just like the measurement scale we use for distance is the only fictional part of those things.
So craig or you suggesting that Einstein is wrong ? That time and space dont exist ? A man a damn site cleverer than you said it does, and it does in a real sense. You cant have speed without distance and time, or are you suggesting that a train traveling at 100 mph actually isnt ? Delete time and you erase pretty much every other construct of our world.
Sorry Craig, usually your pretty near right, this TIME your very very wrong.
It is said time is slowing down, one day it will stop!, then it will go into reverse, like an elastic band. I wonder how many times it has all repeated itself ?. All theories of course, we don`t really know…Still we can go back in time or should that be stop time ?.
http://www.youtube.com/results?search_query=mitchell+and+kenyon&search_type=&aq=f
Einstein was not a time-realist. For example, he said: “When forced to summarize the general theory of relativity in one sentence: Time and space and gravitation have no separate existence from matter.”
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The idea that time is a fourth dimension is a high-school conception of Einstein’s theory: about the level of the Dr Who audience, as it happens. It’s not part of relativity theory – although it often features in introductory texts.
When I asked my physics teacher what time was, he replied that it was what clocks keep. I think it was a good answer.
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We need time in order to communicate. Words are made up different sounds arranged over time. If it turned out that time doesn’t really exist then I for one would be speechless, frankly.
Aha!
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Clark, you’re now coming right out with your theories of consciousness and the universe. You were being a bit coy before.
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“Time travel into the past contravenes free will. The conditions for free will are that the future must be unknowable, and the past must be unchangeable.
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I find it very interesting that physical law seems to outlaw anything that would contravene free will. Our universe seems to be a place where morals matter. Our actions can’t be undone.”
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First of all I don’t think that contravening free will is an argument against anything and I don’t agree with your statement that physical law “outlaws anything that contravenes free will”. Unfortunately I don’t think the Universe cares about morals at all and if the Universe seems to demonstrate at least one thing it is that it is pretty indifferent to good and bad.
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I tend to agree with Nextus on the likelihood of compatibilism. It certainly seems – intuitively – as though we have “free will” although what “free will” actually is is difficult to define.
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“Common-sense determinism was overturned by counter-intuitive quantum physics, but then determinism couldn’t support free will.
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Morals are the foundation of our universe.”
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Clark, I am afraid that these are just bare assertions. What do these assertions actually mean though? “Morals are the foundation of our universe.”?
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“The universe is not divided into “subjects” and “objects”. That was a distinction invented by humans, and then mistaken for reality. This is what the Eastern philosophies have been telling us for centuries.”
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I think East and West is a distinction invented by humans and then mistaken for reality. However, while there is no “objective East” there appears to be a “subjective East”. Is it a matter of reality that I live in the East and you live in the West or do I mean nothing when I say this?
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“Such philosophers need to suspend their concept of self, and embrace Universal consciousness.”
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Aren’t you just contradicting yourself here? Or is that possible when there is no self?
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Watch and learn…
http://www.youtube.com/watch?v=8Q_GQqUg6Ts
As I see it we are morally accountable and indeed our own individual passage or journey through time from birth to death can be visualised as a historical tube running through dark energy, the connecting ‘glue’ that accounts for three quarters of our own accelerating universe. A universe that is continually pushing matter apart to prevent a convergence that ultimately chokes free-will. Convergence is a property of meaningless matter that forms just 5% of the cosmos and ultimately must decay back into particles.
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The indeterminism of matter is a hindrance which we are tasked to overcome in order to pass through into another place where free-will rules and where time and matter are left behind. The existence of this place so close to our own universe is evident in the dark matter leaking through a conduit of dark energy. It is through this conduit that our souls will pass if we are morally able. In short then our universe is a breeding ground for purity or not and the pure move on in a true convergence of minds that are free spirited and liberated to evolve further.
It is only in the realms of consciousness that time exists.
Maxwell’s equations, which precede Einstein’s relativity, are part of the ‘classical’ repertoire of physics; and they yield the solution for the speed of light as being equal to the product of the inverse square roots of the electric and magnetic constants respectively, of free space; physical quantities that can be readily measured.
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It was this ‘physical quality’ of the void of space vacuum, which lead to the notion of the ‘ether’, that in turn inspired the Michaelson-Morely experiment to measure said ‘ether wind’, and Einstein’s famous 1905 paper to account for its lack of results.
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Decades on, and the discredited ether hypothesis finds new life in the quantum physics that allow for the momentary formation and annihilation of ‘virtual’ particles. This being ‘allowable’ owing to the ‘Energy-Time Uncertainty Principle’ that stems from wave-particle duality.
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So the stuff we call the ‘vacuum of space’ is really quite busy, owing to the uncertainty of time itself at the Planck dimensions (sub-atomic scale). Therefore, Craig, time exists, albeit in uncertain lengths, or all the particles of the universe would be unable to interact. In which case, who wrote this blogg, and who is reading it?
Angrysoba, I have no intention of being “coy” here, or are you referring to our private communication? However, not all of these concepts translate easily to blog-comment format.
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Yes, the universe is indifferent to our personal conceptions of “good” and “bad”. But it is not indifferent to creativity and diversity. All our studies of the universe show it to be powerfully creative – the further back in time we look, the less diversity we find. This runs completely counter to what we would expect, for instance from consideration of thermodynamics.
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We can choose to align ourselves with the universal creativity or not, as we wish. That is a moral decision.
Anon, you wrote “It is only in the realms of consciousness that time exists”.
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Consciousness is universal.
I think you might just as well say that distance is an abstract concept..
Angrysoba, yes, I wrote ““Common-sense determinism was overturned by counter-intuitive quantum physics, but then determinism couldn’t support free will.”
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OK, I’ll strip that down a bit. “Quantum physics overturned determinism”. Yes, that is an assertion, but hardly baseless. It was established experimentally when Alain Aspect’s experiments supported only one side of Bell’s inequality.
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Linguistic distinctions such as “East/West” and “Subject/Object” are conveniences necessary to language. They are both meaningful and incomplete.
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As to the rest, I may seem to remain inscrutable, but really, it is up to each to come to their own understanding.
“Yes, the universe is indifferent to our personal conceptions of “good” and “bad”. But it is not indifferent to creativity and diversity. All our studies of the universe show it to be powerfully creative – the further back in time we look, the less diversity we find. This runs completely counter to what we would expect, for instance from consideration of thermodynamics.”
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Well, at least that would certainly show a real direction of time through asymmetry between the past and the present. Yet, doesn’t entropy suggest that the arrow of time points away from creativity and diversity – in the long term – and makes it impossible leading ultimately to the heat death of the universe?
“We can choose to align ourselves with the universal creativity or not, as we wish. That is a moral decision.”
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I have a hard time understanding how you posit the existence of moral agents capable of free will and at the same time deny there is such thing as a self.
Angrysoba, yes, your question about entropy was exactly the unexplained thing I was drawing attention to. Regarding this, and your second point:
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“I think mysticism might be characterized as the study of those propositions which are equivalent to their own negations. The Western point of view is that the class of all such propositions is empty. The Eastern point of view is that this class is empty if and only if it isn’t”
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Raymond Smullyan, This Book Needs No Title, 1980
“Seek freedom, and become captive of your desires. Seek discipline, and find your liberty”