The flow of time is an illusion, and I don’t know very many scientists and philosophers who would disagree with that, to be perfectly honest.
Oh humbug! I have seen many proofs that rely on time going in a particular direction. For example, when solving the wave equation for electromagnetics it it is customary to discard anticausal solutions.
I'm not sure what he means by "flow of time" but I don't think he meant what you argued against. I think he's arguing against the notion that time is like some sort of continuum like a river, or like an axis on a map.
I got the same impression. People are assuming that by 'flow' he means uni-directional, as in the arrow of time. He is talking about the fact that 'flow' semantically implies something that moves, but movement itself requires time. So to say that time flows would be circular reasoning.
To be sure, we also typically throw away imaginary roots when factoring polynomials, since they'd represent nonphysical solutions. But the imaginary bits do come in handy for, well, nonphysical solutions, like measuring phase angle.
So while I tend to side with you that the philosophy bit is probably unnecessary, I would contend that there may be surprising usefulness in the nonsense solutions (or they're just nonsense; it's hard to tell looking at the future work that hasn't been done yet).
As I understood the article, he's neatly sidestepped most of those proofs with his definition of "the flow of time". He agrees that certain properties are associated with their direction along the time axis (e.g. entropy increase in the futureward direction, memories are only available of pastward events). Is suspect that he would also argue that throwing out the anti-causal solutions to the wave equation is nothing more that customary, and that Merlin and Chris Nolan would customarily discard causal solutions and keep only the anti-causal ones.
What was frustrating for me was that he didn't seem define "the flow of time". I would have defined it as the idea that the universe is not translation invariant along the axis measured by clocks. The truth of that statement is practically tautological, as he already agreed that clocks do measure intervals and that measurement inherently breaks the translation symmetry. Then again, cosmology isn't my field so maybe I'm missing something.
"Suppose I stand up, twirl around a few times, and stop. Then I have the overwhelming impression that the entire universe is rotating. I feel it to be rotating—of course I know it’s not."
According to relativity, isn't the view that the universe is rotating just as valid as the view that you are rotating? It all depends on your perspective, and there is no privileged (absolute) vantage point or perspective.
Isn't that so? And if it is so, how can this physicist be ignorant of this?
[Update: Oops. I missed the "and stop" bit. That's what I get for reading HN while I'm half asleep. Sorry!]
Relativity doesn't apply to acceleration. If there were two bodies in the universe, and one accelerated away from the other, it doesn't depend on perspective. Each body is capable of independently determining whether it was the one accelerating, and both would come to the same conclusion.
The same applies to rotation. Accelerometers placed on my floor and on my body will detect the difference, and both will agree.
My interpretation of that quote is that he is referring to his impression after he stops. That's why he specifically references the stopping. You may be familiar with the experience - twirl around for a little bit then stop, and you will feel like the world ("entire universe"?) is still spinning. Even though it's not.
Of course, I may be ignorant of his actual intent.
Special relativity says that there is no privileged perspective with respect to linear velocity, but general relativity showed that rotating reference frames are different, since one frame sees a centripetal forces while the other frames sees a centrifugal/gravitational force.
To put it differently, if I pass someone on the train moving at constant velocity, there's no experiment that I can perform which proves that I'm moving while the other person is standing still, or vice versa.
However, if I'm in a centrifuge, instead of on a train, then I can figure out which one of us is moving by measuring who is pressed up against the wall and making funny faces.
No, I think the point is that your mind interprets the universe as spinning when you stop twirling. This is just an interpretation, as is the flow of time.
An important implication of relativity is that when you push something, you do not change it's velocity. You change it's acceleration. It's a small but important distinction. Acceleration is more fundamental.
I can't quite get a feel for the background and slant of some of these new web-only publications. I'm thinking of nautil.us and aeon.co in particular. They are science-focused, but lean toward philosophical topics.
I can't figure out if they are reputable sources that dabble in more abstract concepts, or if they are some kind of pseudo-science platform for crazy founders.
I'm the "crazy" founder of Nautilus. We are a science magazine, with a multidisciplinary approach. We want to explore each monthly issue topic from disciplines within and outside the sciences, like philosophy. But we are mostly about telling good stories....science with a literary voice.
Aeon is overtly anti-scientific in all the articles from it I've read. The trend tends to be to take something scientific, like cognitive biases or the Milgram experiments, use some postmodernist device like Freudian literary criticism or political theory to critique the science, and then conclude that the factual reality is not in favor of the scientific evidence.
Just to note -- Nautilus is also a print publication! I have their substantial (nearly 200 pages), beautiful (simple and effective layout, thick glossy pages), and fascinating Fall 2014 issue on the table in front of me. I've made a conscious effort to read more physical books lately, because tablets and even Kindle holds too many temptations for my distractable self. When I'm not quite in a book mood, it turns out that a high-quality periodical like Nautilus is still very wonderful, even in our webby world.
Time, like space, is a relational concept -- e.g. the motion of an entity relative to the motion of another, and the position of an entity relative to that of another. Observe that we measure time in terms of the repetitive motion of chosen entities.
But very cold entities - almost not moving. The latest 'atomic' clock uses "spin-polarized, ultracold atomic ytterbium". Its not the particle motion per se that's being measured; its fields around the particle, right? Not at all relative motion.
Aren't these fields thought to be even smaller particles? Like the hypothetical graviton. So everything could be made of particles, even forces like gravity.
"Of course events in the world follow a directional sequence. Drop an egg on the floor and it breaks. You don’t see eggs assembling themselves."
The operative phrase here being "you don't see". Of course, seeing is a matter of perception and perspective. It could very well be that time is flowing "backwards" and eggs are in fact reassembling themselves, but we are just perceiving time in reverse.
You know, when I hear physicists try to tackle philosophical problems, it's usually kind of embarrassing. These guys are rarely trained in philosophy and are out of their depth.
As Feinman famously said to his own students, "Shut up and calculate."
I wish more physicists would follow his advice, and leave philosophy to philosophers.
Shame on you. Nobody should be discouraged from trying to dabble in things that aren't their field.
Having the background of being extremely well-trained in one field gives a different perspective than the typical "echo-chamber" of the elite in any specialty.
If you know something they don't, why not try to start a dialog instead of criticizing and dismissing?
Perhaps I'm being too harsh, but I only criticize because they're often given a soapbox (such as in this article) due to the perception that they are specially endowed with the power of "explaining how the world is" to us mere mortals.
Well, that wouldn't be so bad if they stuck to explaining the results of their experiments, but when they stray from that on to philosophical subjects, they're really no more suited to talking about that than any other non-philosophically trained layman.
It might help if they toned down the rhetoric a bit and make it clear that they're speaking about something that they have no training in.
On the other hand, I suppose I should be grateful that they're exposing the general public to ideas they might not have otherwise thought about, even if they do so clumsily and their conclusions are highly suspect.
I would contend that having a high degree of education in anything develops certain thinking abilities that are widely transferable. At some point, they transform from being a "layman" into being an "amateur philosopher" simply by virtue of these transferable thinking skills.
Of course being an amateur doesn't lend a high degree of credibility, but certainly more than the average Joe.
They don't need to ignore philosophy entirely, they just need to recognise that it's a different subject, and that studying physics is not sufficient to understand it, nor is it necessarily going to give them any unique insight.
Well, Frank Wilczek said something like "Philosophy is too important to be left to the philosophers." [0] The unspoken assumption is that those silly philosophers are off writing a priori worthless post-Marxist historiographic treatises and other humanities BS, so the real men (physicists) are going to have to storm in guns a blazin' and sort things out.
Being neither a philosopher nor physicist by training, I'm probably unqualified to arbitrate that debate. But it is worth noting that when qualitative approaches meet quantitative approaches, the quant guys seem to pretty persistently come out on top (e.g. Google with programmatic advertising vs. the good old boys selling ads by taking the client out to a steakhouse. Which model overwhelmed the other in mere months?)
"it is worth noting that when qualitative approaches meet quantitative approaches, the quant guys seem to pretty persistently come out on top"
One could certainly make the argument that the practice of science and the creation of technology "gets results" (though there are counter-arguments having to do with human agency or free will, with causality, and with our perception of the world and whether what we perceive is real and whether what looks like obvious cause and effect is actually what's going on here).
But whether something "gets results" may have little bearing on whether it is true or an adequate explanation of the world.
The point is that we don't see eggs break at some times and reassemble themselves at others. Whether time is flowing "forwards" or "backwards" is just a label - if you decided to start calling "tomorrow" "yesterday", it wouldn't change anything except what you say.
However, if you could break an egg and then unbreak it, that would be remarkable (and observable), whether you did it tomorrow or yesterday.
Where it’s particularly striking of course is when people respond appropriately much faster than the speed of thought. You need only think of a piano player or a tennis player to see that the impression that they are making a conscious decision—“that ball is coming in this direction; I’d better move over here and hit it”—couldn’t possibly be.
If it isn't conscious thought and motor signals, then what is it?
This dichotomy implies a dualism, as if there's a clear cut "I" and then there's "my mind". In fact, our mind is us, and it working 'without us knowing' is just 'it working without verbalization of our thoughts' which is a different thing I'd say.
In conscience thoughts and motor signals. I think the point is, that after the match, the player can be asked "what went through you head when..." And they will answer as if during the game they made a conscience judgement of the entire situation.
And when people are asked "what do you think of band X" for an X which does not exist, they may answer you as if X existed. And later they may even forget that they were fabricating and come to believe it themselves.
Memory is reconstructive. Memory is aspirational. Memory is an evolutionary adaptation. Memory is lossy and iterative. Memory is an unconscious advantage-seeking collaborator.
People are (for whatever reasons) given more credit for conscious decisions than for unconscious reflexes, so it is in their interest to make it seem as if their actions were under conscious control. So memory does that for them.
I think he's saying that the in-game thinking is unconscious (fast, practiced, muscle-memory) but remembered as conscious, and it must be the former because things are happening too fast.
"For example, there are famous experiments in which people apparently make free decisions at certain moments and yet it’s found that the decision was actually made a little bit earlier, but their own perception of time and their actions within time have been sort of edited after the event"
This would also be the only way to simulate consciousness in AI. Makes total sense. We're AI.
The question that's always in my mind is if the perception of the flow of time is really just entropy. As long as state A is different than state B we have a perception of time.
Sure. In a cold vacuum with no atoms at all, those conditions are satisfied (no movement of any kind). But the vacuum continues to generate particle pairs and annihilate them; EM radiation continues to propagate. All on a strict clock.
I think this one runs some risk of begging the question, though, so unless we make it significantly more precise we're unlikely to get anything useful out of it.
I don't think that's true, depending partly on how we define "could", but we're getting off into the weeds. In this case, we're trying to understand aspects of the laws of physics; getting at the consequences if they differed subtly could be tremendously useful - akin to a proof by contradiction.
> getting at the consequences if they differed subtly could be tremendously useful
Sure, but that doesn't describe "What if radiation and quantum noise stopped moving?". That's just a dumb question. We can't really derive anything interesting from its consideration. It's along the lines of "What if you dropped a rock and it didn't fall?" What if?
If you dropped a rock and it didn't fall, you could infer that probably either you are outside an appreciable gravitational field or there's some force counteracting the gravitational field you're in.
In any event, I agree that the question is not likely to be useful, but as I said I think that is because it subtly begs the question in a way that isn't likely to be clear without it being stated quite a bit more formally.
"That's just a dumb question."
While "there are no dumb questions" is an overstatement, I think your tone throughout this has been unnecessarily hostile (not toward me, mind you). You could have done more to educate, you chose to abuse, and in a way that stepped into inaccuracy to boot.
>If you dropped a rock and it didn't fall, you could infer that probably either you are outside an appreciable gravitational field or there's some force counteracting the gravitational field you're in.
Perhaps my example was not appropriate, because I described something that could happen (which is what might allow us to have a useful thought experiment). I couldn't think of anything to match the irrelevance or off-basedness of the radiation-stopping question.
>You could have done more to educate, you chose to abuse
"Abuse" is quite hyperbolic in this situation. And you're right, I could have done more to educate, but I also don't have infinite time to give helpful and constructive corrections to every stupid comment on the internet. Sometimes you just make it clear that the comment is stupid, so no one else accidentally takes it as reasonable, and leave.
I certainly didn't mean it in its strongest sense.
"I also don't have infinite time to give helpful and constructive corrections to every stupid comment on the internet."
But you have time to give poor responses. I suggest you reorganize your time.
"Sometimes you just make it clear that the comment is stupid, so no one else accidentally takes it as reasonable, and leave."
I don't think that's what it tells people. You didn't explain, in a useful way, why it was unreasonable. So all people know is 1) someone on the internet thinks this comment sucks (which is almost tautological), and 2) comments are more likely to be met with negativity than assistance (which is harmful to our community).
Correct. All EM Radiation has a frequency ( spectrum ) . The spectrum is useful because it selects which barionic matter interacts with it. This interaction is what we feel as time due to the statistics of the interations ( less events vs. many more ).
"Make yourself a question, if ALL movement stop (include atoms), will time pass?"
That's pretty much asking "If time stops, will time pass?" - which doesn't really answer anything. Stopping all movement is not something we ever see in the universe (well, we couldn't see or experience it anyway). And yet we see movement - we see everything changes.
I think time may be a human construct to order these changes, but it is also a property of the universe (whether fundamental or emergent) which allows such change to happen in the first place.
If time is just movement, time is not a particular property of the universe, just a construction of ours as observers.
Then the universe is matter, space and movement, and "time" is one useful illusion to ourselves, but it is not a property of the universe.
If "time is just movement", then it is an emergent property of the universe (and movement, or more generally - change, would be the fundamental property). Still it wouldn't mean that time is just a construct we created, as it would be firmly rooted in the underlying fundamental property (the movement you mentioned).
If on the other hand it is the opposite (and based on the way we experience universe, I'd rather think it is the opposite) - then "movement" would be the emergent property of space and time; and both space and time would be more fundamental properties.
In either case I don't think "illusion" is the right word, as it implies something non-existent or unreal. And even if it is an emergent property, it would still emerge from some more fundamental properties and thus would be quite real.
Because we're part of the system, so that might not be possible... and if it is, then because that feeling wouldn't be useful if no causal arrows point that way.
I'm confused why they spent so much time on the idiom of "flowing" time. It doesn't literally feel like it's "flowing", that's just a figure of speech, a metaphor for the fact that in daily life we don't have control over its direction.
While the implications and meaning of time in a cosmological sense are certainly interesting, the piece's angle of debunking naive common-sense views of time is a bit too aggressive. In daily life, the common-sense view of time is perfectly rational.
Perhaps the audience is physics grad students, I dunno.
>It doesn't literally feel like it's "flowing", that's just a figure of speech, a metaphor for the fact that in daily life we don't have control over its direction.
Huh? The flow of time, and "time passing" is the most universal and common understanding (and feeling) of time.
Yes, these are common metaphors. They do not describe the actual perceptual experience of the passage of time. To get hung up on what metaphors people use to describe something utterly intangible is silly.
I found this BBC documentary to be such an engaging piece. It challenges our perception of time. It is difficult to reconcile it with everyday demands of referring to a clock to guide our progression through the day.
I highly recommend this documentary as well. Thanks for posting it, I will be listening to it again today.
When you talk about what is the rate of a clock, say, near the surface of a black hole, it’s going to be quite different from the rate of a clock here on Earth. So there isn’t even a common time in the entire universe.
Well, isn't there a common time for the entire universe? If we ignore being near massive objects, then observers travelling with the expansion of the universe - i.e. those those who don't see a dipole in the cosmic microwave background (CMB) - then the redshift of the CMB acts as a kind of clock. With the usual cosmological assumptions of isotropy and homogeneity, then there's a big clock for everyone to use.
I read the book and watched the documentary, "The Fabric of the Cosmos" by Brian Greene.
He gave a good explanation of time. Right before the big bang, the universe was in a 'perfectly' ordered state. Since the big bang the universe has become less and less 'perfect'. What we think of as Time is really just things getting less and less organized.
>Where it’s particularly striking of course is when people respond appropriately much faster than the speed of thought. You need only think of a piano player or a tennis player to see that the impression that they are making a conscious decision—“that ball is coming in this direction; I’d better move over here and hit it”—couldn’t possibly be. The time it takes for the signals to get to the brain and then through the motor system, back to the response, couldn’t work. And yet they still have this overwhelming impression that they’re observing the world in real time and are in control. I think all of this is pretty fascinating stuff.
I see this repeated to point that "hence we are not really conscious" or not really in control of ourselves.
But, to me, an obvious answer is that our "thought" is not just the "talk-to-myself" like thought, but also faster unconscious processes, that still weights things and combines our memories and "personality" biases in the decision making, it's just not like an 'inner-dialogue'
For those interested in understanding why we conceive of time the way we do, I recommend Philosophy in the Flesh, by Lakoff and Johnson. Chapter 10 deals with Time.
And the other thing people contemplate: They think denying the flow of time is denying time asymmetry of the world. Of course events in the world follow a directional sequence. Drop an egg on the floor and it breaks. You don’t see eggs assembling themselves. Buildings fall down after earthquakes; they don’t rise up from heaps of rubble.
"Events occurring in sequence" is the same thing as "the flow of time", in my understanding at least. What else does "the flow of time" refer to? I fear there's a subtle point being made that I don't quite grasp.
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[ 3.9 ms ] story [ 169 ms ] threadI kind of suffered through Physics in undergrad but this makes me wish I took more as an elective.
So while I tend to side with you that the philosophy bit is probably unnecessary, I would contend that there may be surprising usefulness in the nonsense solutions (or they're just nonsense; it's hard to tell looking at the future work that hasn't been done yet).
What was frustrating for me was that he didn't seem define "the flow of time". I would have defined it as the idea that the universe is not translation invariant along the axis measured by clocks. The truth of that statement is practically tautological, as he already agreed that clocks do measure intervals and that measurement inherently breaks the translation symmetry. Then again, cosmology isn't my field so maybe I'm missing something.
According to relativity, isn't the view that the universe is rotating just as valid as the view that you are rotating? It all depends on your perspective, and there is no privileged (absolute) vantage point or perspective.
Isn't that so? And if it is so, how can this physicist be ignorant of this?
[Update: Oops. I missed the "and stop" bit. That's what I get for reading HN while I'm half asleep. Sorry!]
The same applies to rotation. Accelerometers placed on my floor and on my body will detect the difference, and both will agree.
Of course, I may be ignorant of his actual intent.
To put it differently, if I pass someone on the train moving at constant velocity, there's no experiment that I can perform which proves that I'm moving while the other person is standing still, or vice versa.
However, if I'm in a centrifuge, instead of on a train, then I can figure out which one of us is moving by measuring who is pressed up against the wall and making funny faces.
http://en.wikipedia.org/wiki/Mach's_principle
An important implication of relativity is that when you push something, you do not change it's velocity. You change it's acceleration. It's a small but important distinction. Acceleration is more fundamental.
I can't figure out if they are reputable sources that dabble in more abstract concepts, or if they are some kind of pseudo-science platform for crazy founders.
I think it's just generic post-modernism.
Isn't time (like darkness) merely a description of a state of space / matter?
It was/wasn't here, now it's here?
The operative phrase here being "you don't see". Of course, seeing is a matter of perception and perspective. It could very well be that time is flowing "backwards" and eggs are in fact reassembling themselves, but we are just perceiving time in reverse.
You know, when I hear physicists try to tackle philosophical problems, it's usually kind of embarrassing. These guys are rarely trained in philosophy and are out of their depth.
As Feinman famously said to his own students, "Shut up and calculate."
I wish more physicists would follow his advice, and leave philosophy to philosophers.
Having the background of being extremely well-trained in one field gives a different perspective than the typical "echo-chamber" of the elite in any specialty.
If you know something they don't, why not try to start a dialog instead of criticizing and dismissing?
http://www.paulgraham.com/philosophy.html
Well, that wouldn't be so bad if they stuck to explaining the results of their experiments, but when they stray from that on to philosophical subjects, they're really no more suited to talking about that than any other non-philosophically trained layman.
It might help if they toned down the rhetoric a bit and make it clear that they're speaking about something that they have no training in.
On the other hand, I suppose I should be grateful that they're exposing the general public to ideas they might not have otherwise thought about, even if they do so clumsily and their conclusions are highly suspect.
Of course being an amateur doesn't lend a high degree of credibility, but certainly more than the average Joe.
Being neither a philosopher nor physicist by training, I'm probably unqualified to arbitrate that debate. But it is worth noting that when qualitative approaches meet quantitative approaches, the quant guys seem to pretty persistently come out on top (e.g. Google with programmatic advertising vs. the good old boys selling ads by taking the client out to a steakhouse. Which model overwhelmed the other in mere months?)
[0] http://frankwilczek.com/unification.html
One could certainly make the argument that the practice of science and the creation of technology "gets results" (though there are counter-arguments having to do with human agency or free will, with causality, and with our perception of the world and whether what we perceive is real and whether what looks like obvious cause and effect is actually what's going on here).
But whether something "gets results" may have little bearing on whether it is true or an adequate explanation of the world.
However, if you could break an egg and then unbreak it, that would be remarkable (and observable), whether you did it tomorrow or yesterday.
If it isn't conscious thought and motor signals, then what is it?
For example, our mind processes thousands (or millions) of signals coming from our senses without us needing to "think" about it.
https://news.ycombinator.com/item?id=8519764 ("We Are All Confident Idiots")
Memory is reconstructive. Memory is aspirational. Memory is an evolutionary adaptation. Memory is lossy and iterative. Memory is an unconscious advantage-seeking collaborator.
People are (for whatever reasons) given more credit for conscious decisions than for unconscious reflexes, so it is in their interest to make it seem as if their actions were under conscious control. So memory does that for them.
This would also be the only way to simulate consciousness in AI. Makes total sense. We're AI.
All our "time" measures are based on cyclics movements.
Make yourself a question, if ALL movement stop (include atoms), will time pass? will the arrow of time advance?
It is generally not useful to consider the consequence of falsehoods.
http://en.wikipedia.org/wiki/Thought_experiment
I think this one runs some risk of begging the question, though, so unless we make it significantly more precise we're unlikely to get anything useful out of it.
Sure, but that doesn't describe "What if radiation and quantum noise stopped moving?". That's just a dumb question. We can't really derive anything interesting from its consideration. It's along the lines of "What if you dropped a rock and it didn't fall?" What if?
In any event, I agree that the question is not likely to be useful, but as I said I think that is because it subtly begs the question in a way that isn't likely to be clear without it being stated quite a bit more formally.
"That's just a dumb question."
While "there are no dumb questions" is an overstatement, I think your tone throughout this has been unnecessarily hostile (not toward me, mind you). You could have done more to educate, you chose to abuse, and in a way that stepped into inaccuracy to boot.
Perhaps my example was not appropriate, because I described something that could happen (which is what might allow us to have a useful thought experiment). I couldn't think of anything to match the irrelevance or off-basedness of the radiation-stopping question.
>You could have done more to educate, you chose to abuse
"Abuse" is quite hyperbolic in this situation. And you're right, I could have done more to educate, but I also don't have infinite time to give helpful and constructive corrections to every stupid comment on the internet. Sometimes you just make it clear that the comment is stupid, so no one else accidentally takes it as reasonable, and leave.
I certainly didn't mean it in its strongest sense.
"I also don't have infinite time to give helpful and constructive corrections to every stupid comment on the internet."
But you have time to give poor responses. I suggest you reorganize your time.
"Sometimes you just make it clear that the comment is stupid, so no one else accidentally takes it as reasonable, and leave."
I don't think that's what it tells people. You didn't explain, in a useful way, why it was unreasonable. So all people know is 1) someone on the internet thinks this comment sucks (which is almost tautological), and 2) comments are more likely to be met with negativity than assistance (which is harmful to our community).
That's pretty much asking "If time stops, will time pass?" - which doesn't really answer anything. Stopping all movement is not something we ever see in the universe (well, we couldn't see or experience it anyway). And yet we see movement - we see everything changes.
I think time may be a human construct to order these changes, but it is also a property of the universe (whether fundamental or emergent) which allows such change to happen in the first place.
If on the other hand it is the opposite (and based on the way we experience universe, I'd rather think it is the opposite) - then "movement" would be the emergent property of space and time; and both space and time would be more fundamental properties.
In either case I don't think "illusion" is the right word, as it implies something non-existent or unreal. And even if it is an emergent property, it would still emerge from some more fundamental properties and thus would be quite real.
While the implications and meaning of time in a cosmological sense are certainly interesting, the piece's angle of debunking naive common-sense views of time is a bit too aggressive. In daily life, the common-sense view of time is perfectly rational.
Perhaps the audience is physics grad students, I dunno.
Huh? The flow of time, and "time passing" is the most universal and common understanding (and feeling) of time.
https://www.youtube.com/watch?v=4BjGWLJNPcA
I highly recommend this documentary as well. Thanks for posting it, I will be listening to it again today.
Well, isn't there a common time for the entire universe? If we ignore being near massive objects, then observers travelling with the expansion of the universe - i.e. those those who don't see a dipole in the cosmic microwave background (CMB) - then the redshift of the CMB acts as a kind of clock. With the usual cosmological assumptions of isotropy and homogeneity, then there's a big clock for everyone to use.
He gave a good explanation of time. Right before the big bang, the universe was in a 'perfectly' ordered state. Since the big bang the universe has become less and less 'perfect'. What we think of as Time is really just things getting less and less organized.
[1] http://www.amazon.com/gp/product/B000XUDGV2?btkr=1
I see this repeated to point that "hence we are not really conscious" or not really in control of ourselves.
But, to me, an obvious answer is that our "thought" is not just the "talk-to-myself" like thought, but also faster unconscious processes, that still weights things and combines our memories and "personality" biases in the decision making, it's just not like an 'inner-dialogue'
http://www.nytimes.com/books/first/l/lakoff-philosophy.html
"Events occurring in sequence" is the same thing as "the flow of time", in my understanding at least. What else does "the flow of time" refer to? I fear there's a subtle point being made that I don't quite grasp.