Why do we need philosophy? There are several reasons, but one is to expose the confusions and absurdities of scientists and science journalists when they encroach ineptly upon philosophical territory. This from science writer Clara Moskowitz in Controversially, Physicist Argues Time is Real:
NEW YORK — Is time real, or the ultimate illusion?
Most physicists would say the latter, but Lee Smolin challenges this orthodoxy in his new book, "Time Reborn" (Houghton Mifflin Harcourt, April 2013) . . . .
Time is an illusion? And this is supposed to be orthodoxy? But don't the cosmologists tells us that the universe began in a Big Bang some 12-13 billion years ago? If time is an illusion, then that statement and statements like it cannot be true. For if time is "the ultimate illusion," , then it is never true that event x is earlier than event y, that y is later than x, or that x and y are simultaneous (whether absolutely or relative to a reference-frame). But surely the Big Bang is earlier than my birth, and my blogging is later than my having had breakfast. If time is an illusion, however, then the so-called B-relations (as the philosophers all them) cannot be instantiated. The B-relations are: earlier than, later than, and simultaneous with. Physics cannot do without them. If time is an illusion, then it cannot be true that the speed of light is finite (in a vacuum, approx. 186, 282 mi/sec). But it is true, and because of it, sunlight takes time to arrive at Earth (about 8 min 19 sec). It arrives later (temporal word!) than it started out. Therefore, time cannot be an illusion.
My first point, then, is that the physicists themselves presuppose that time is not an illusion by the very fact that they employ such phrases as 'earlier than,' 'later than,' 'simultaneous with,' and a host of other temporal words and phrases. Suppose two cosmologists are discussing whether the universe began 15 billion years ago or 12 billion years ago. Debating this point, they presuppose that time is precisely not an illusion. The past-tensed 'began' and the little word 'ago' make it clear why. Reading on we come to this:
In a conversation with Duke University neuroscientist Warren Meck, theoretical physicist Smolin, who's based at Canada's Perimeter Institute for Theoretical Physics, argued for the controversial idea that time is real. "Time is paramount," he said, "and the experience we all have of reality being in the present moment is not an illusion, but the deepest clue we have to the fundamental nature of reality."
Time is paramount? No doubt! No time, no physics. All of reality is in the present moment? So what happened in the past is not part of reality? When we inquire into what happened, whether as historians or as cosmologists, what then are we inquiring into? Unreality? Mere possibility? Fiction? Do you really want to say that all of reality is in the present moment? There is a deep confusion here (whether it is chargeable to Smolin's account or the science writer's, I don't know): It one thing to affirm the doctrine of presentism according to which only the temporal present and its contents are real; it is quite another to affirm, as Smolin seems to be doing, that time is not exhausted by the B-series, the series of events ordered by the above-mentioned B-relations.
Smolin said he hadn't come to this concept lightly. He started out thinking, as most physicists do, that time is subjective and illusory. According to Albert Einstein's theory of general relativity, time is just another dimension in space, traversable in either direction, and our human perception of moments passing steadily and sequentially is all in our heads.
We now see what is really going on here. Smolin is not opposing the claim that time is an illusion, but the claim that time is exhausted by the B-series, where the B-series (this term from McTaggart) is the series of events ordered by the B-relations. Clearly, there is a difference between saying that time is real, but exhausted by the B-series, and saying that time is unreal. There is nothing particularly controversial about maintaining that time is real. What is controversial is to maintain that real time involves not only the instantiation of the B-relations but also the (shifting) instantiation of the irreducible A-properties, pastness, presentness, and futurity.
As we ordinarily think of it, time passes, flows, indeed 'flies.' Tempus fugit! as the Latin saying goes. We think of events approaching us from the future, getting closer and closer until they become present, and then receding into the past becoming ever more past. Thus, as a natural man, I think of my death as approaching, becoming less and less future, and my birth as receding, as becoming more and more past. This belief in the reality of temporal becoming (as some philosophers call it) is part and parcel of our ordinary view of the world. But physics, pace Smolin, needn't concern itself with it.
Now it is not unreasonable to think of temporal passage or temporal becoming as a mind-dependent phenomena such that, in reality, there is no temporal becoming, and no (shifting) exemplification of the A-properties. All there is are events ordered by the B-relations. But this is not to say that time is an illusion but that real time is exhaustively analyzable in terms of the B-relations. Note also that if temporal becoming is mind-dependent, it doesn't follow that it is an illusion. Phenomenal colors are m ind-dependent but not illusory.
There is more, but it doesn't get any better, and I have exposed enough confusions for one day. To sum up:
1. One ought not confuse the claim that time is an illusion with the claim that time is exhausted by the B-series.
2. That time is real is presupposed by both common sense and the practice of physicists.
3. One ought not confuse presentism, the view that only the temporally present exists, with the claim that there is more to time than the B-series.
4. One ought not confuse the claim that temporal becoming is mind-dependent with the claim that temporal becoming is an illusion.
5. One ought not confuse the claim that temporal becoming is an illusion with the claim that time is an illusion, or the claim that time is real with the claim that temporal becoming is real.