There are 2 paradoxes in relativity

 This post is based on an interaction I had on Quora. When people discuss the twin paradox (like I did), they always discuss the difference in time, each twin experiences relative to the other; they don’t discuss the difference in distance they experience, which is a logical consequence of the same Lorenz transformation. 

However, someone on Quora conjectured that in reality, the clocks actually measure time at the exact same rate and it’s the distance that changes. Mathematically, there is nothing wrong with this argument, so why do I disagree with it?

 

The twin paradox, of course, is a thought experiment, but there is a real-life experiment where this happens, which I’ve also discussed in another post, and that is the half-life of muons in the Earth’s atmosphere. According to the scientists observing them on the Earth’s surface, there are too many of them, which means they took longer to decay (the half-life got longer). But, from the muon’s perspective, their half-life hasn’t changed, it’s just the distance to the Earth was shorter. Now, this creates a paradox, which is equally manifest in the twin paradox thought experiment. 

 

How can the distance change depending on whose perspective you take? I don’t believe it does. I contend that the moving observer ‘measures’ a shorter distance based on their clock slowing down. But, you’ll say, the whole point of relativity is that no one knows who is moving and who is stationary. Well, there is a reference point, which, in the case of the muons, is the gravitational field of Earth. A body in free fall experiences maximum ‘proper’ time and any deviation from that causes a clock to slow down. The fact is, because the muons are travelling at high fractional light speeds, their deviation from maximum proper time is greater than the observers on the ground. I believe this logic also applies to the travelling twin in the thought experiment.

 

If you take this to extremis, someone could hypothetically travel across the entire galaxy in their lifetime if they travelled fast enough (without exceeding the speed of light). From their perspective, the distance would shrink astronomically, but if they returned to Earth, eons would have passed in their absence. I should point out that science fiction writers (like myself) routinely ignore this fundamental consequence of relativity. We ‘imagine’ that humanity has discovered ‘new physics’ to overcome this ‘problem’

 

I’m not sure how heretical it is to argue this: that time changes but the distance doesn’t. if one goes back to the argument that started this rumination: when the twins reunite their respective clocks disagree and the space-faring twin is noticeably younger than their counterpart. However, they not only disagree on the elapsed time, since the space-faring twin’s departure, they also disagree on how far that particular twin travelled. BUT, now that the space-faring twin is back in the same frame of reference as their Earthbound twin, they concur on the distance, yet still disagree on the time elapsed, evidenced by their clocks and age difference.

 

 

Addendum: Ian Miller (PhD in Chemistry and a self-described 'theoretician' on Quora) argues that it's the ruler that changes relativistically and not the distance travelled. And I'd contend that the clock is effectively the ruler.

Existentialism in everyday life

This is a post I wrote on Quora, in answer to the question:

 

If I believe that life is completely meaningless, am I an existentialist or a nihilist?

 

My answer was ‘upvoted’ by Frederick Dolan, who is Professor at UC Berkeley, after I commented on his own answer to the same question.

 

 

Existentialism is often associated with the absurd, thanks to Camus mostly, which is a short step from nihilism in many people’s minds. There is a view among the scientific community that the Universe is meaningless and that the presence of sentient beings is just a freak accident. Paul Davies refers to this view as the ‘absurd universe’, and I tend to agree with him. 

 

The point is that we find meaning in living our lives through relationships and projects, and even through career or vocation. Viktor Frankl elaborated on this in his book, Man’s Search for Meaning, and added a third way, which is through dealing with adversity. This last ‘way’ might appear ‘absurd’ at first glance, but it’s the premise of virtually every story ever told; it’s a universal theme.

 

Sartre argued that we create our own ‘project’ just by living our lives, and this is what existentialism means to me. So I would contend that there is a direct connection between existentialism and the importance of finding meaning in our lives. In fact, having a ‘purpose’ is considered essential to mental health, according to psychologists. If the Universe has any meaning at all, it’s because it created sentient beings who find meaning against the odds that science tells us are astronomical, both literally and figuratively. Existentialism is about finding purpose in an absurd universe, which is the opposite of nihilism.

A philosophical exploration of Type A and Type B time

 This arose from a question referred to me on Quora. As part of my discussion, I wondered into philosophical territory originally posited over a century ago by a forgotten philosopher, J.M.E. McTaggart, thanks to A.C. Grayling (English philosophers seem to have a predilection for using initials). It seems to fit seamlessly into my own particular philosophy on the relationship between time and consciousness.

 

The original question on Quora, asked by Adriana Moraes (from Sao Paulo, Brazil):

 

How does the past, present, and future exist simultaneously?

 

I don’t believe they do. In fact, I contend that past, present and future are only meaningful concepts in some creature’s mind; which means that I don’t believe it’s a cognitive state unique to humanity.

 

We are only aware of the past because we have memories. In fact, without memory, you wouldn’t know you are conscious. Consciousness exists in a constant present, so time for us is always ‘now’. This, of course, applies to all sentient creatures. For all events that we witness or observe, ‘now’ is ephemeral – they become the past as soon as they happen - which is demonstrated every time someone takes a photo. We say it ‘freezes time’, when in fact, it records an event that would otherwise vanish.

 

Past, present and future require a reference point, and consciousness provides that reference point. We imagine futures, and curiously, the same part of the brain that imagines what might happen, conjures up memories of what has happened. This makes sense when one realises that we attempt to predict the future based on what we have experienced in the past. 

 

Raymond Tallis, who has a background in neuroscience and writes books as well as a regular column in Philosophy Now, makes the observation that our ability to ‘imagine’ future ‘possibilities’, and select one to make ‘actual’, is the very definition of free will, only he calls it 'agency'.

 

In 1908, an Oxford philosopher, J.M.E. McTaggart published a paper titled, On the Unreality of Time in the journal, Mind (ref: A.C. Grayling, The History of Philosophy, 2019). McTaggart argued that there are 2 types of time: Type A, which is based on using the ‘present’ as a reference point for ‘past-present-future’; and Type B, which is just the ordering of events into ‘earlier than/later than’. He contended, in effect, that because ‘now’ is constantly changing, you get contradictions with Type A and Type B (which is perceivably 'fixed'). I’ve over-simplified his argument for brevity, and given it my own interpretation, which is that you can’t have both Type A and Type B. However, I contend that Type B time is just Type A time without consciousness, which resolves that particular paradox.

 

Most physicists, if not all, believe that the past, present and future are all fixed, because, according to Einstein’s special theory of relativity, ‘now’ is totally subjective. This is the so-called ‘block universe’, which is a logical consequence of treating time as a spatial dimension, giving us space-time.

 

You can observe time as a dimension by looking at the night sky and seeing stars hundreds, if not thousands of years, in the past. This means that hypothetical observers in different parts of the Universe see a different ‘now’ and will observe events occurring in different sequences. This is a logical consequence of the finite speed of light. However, causally related events must happen in an objective sequence, irrespective of observers. This is Type B time, as defined by McTaggart. We are able to deduce causality of events that have happened in our past, which gives us theories of cosmology and evolution. This has to be compatible with Type A time, which is dependent on the fact that we all live in the present all of the time. 

 

Whether our present is different to someone else’s present (somewhere else in the Universe) just means that their Type A experience of time is different to ours, but Type B time occurs regardless of conscious observers.

Does QM and classical physics create the irreversibility of time?

 At long last I’ve found a YouTube video that pretty much describes quantum mechanics (QM) as I would. In particular, the narrator (Arvin Ash) expresses the possibility that the transition from QM to classical physics provides the irreversibility of time that we all experience in everyday life. In other words, QM describes the future and classical physics describes the past. The narrator cites Lee Smolin, who actually says that QM describes the ‘present’ and classical physics describes the past. Now, I’ve read Lee Smolin’s book, The Trouble with Physics, and, from memory, he made no mention of this, so maybe this is a new idea from him (I don’t know).

My knowledge of QM is rudimentary at best, so I’m hardly one who can judge, but I’ve been thinking this way since I wrote a post called What is now? in 2015. Back then, I didn’t know that Freeman Dyson had similar ideas. A contributor to Quora, Mark John Fernee, who clearly knows a lot more than me, made a similar point about QM to classical physics being irreversible in time, and whom I quoted in a not-so-recent post.

 

Ash also explains entanglement and decoherence without getting too esoteric about it, and seems to promote the view that entanglement, in principle, could involve the whole universe. Decoherence is often explained as the ‘leaking’ of information. The important point is that decoherence (or the wavefunction collapse) comes from the quantum phenomenon interacting with other particles, that one assumes already exist.

 

The narrator conjectures at the end that the multiverse interpretation is still possible, but I’m not so sure. The whole point of MWI (multiple worlds interpretation) is supposedly that decoherence never happens, but this variation means that it still would happen, only in other universes. Sabine Hossenfelder makes a similar point in a YouTube video of her own. 

 

The other problem with MWI, as I see it, is that entanglement would necessarily incorporate a multiverse. I suspect adherents to MWI (and there are a lot of them) wouldn’t have a problem with that, but I don’t really know. Some highly respected physicists, like Sean Carroll, are advocates of MWI. I really admire Sean Carroll and he readily admits that MWI is one of his personal prejudices. I recently saw a talk he gave on ‘time’ for New Scientist, but he didn’t mention any of this. Instead, he talked about the role of entropy, including its ramifications for the evolvement of the entire universe. I’m a heretic on entropy in that I think it’s a consequence of the arrow of time, not its cause. Having said that, the low entropy state of the Universe in the beginning is still a conundrum, though gravity plays a role in increasing complexity in the Universe, in spite of entropy.

 

In another video (by Closer to Truth), Lee Smolin articulates the possibility that time and 

space may be separate after all, which I’m beginning to wonder myself. Besides, if the Universe has a boundary (or edge) in time, but not in space, that would infer that they are separate. We know that time on a cosmic scale is finite, because we can estimate the age of the Universe.

 

I believe we all live on the edge of time (all of the time), which is contentious. All physicists, that I read and listen to, argue that there is no universal now, and I’m told that to think otherwise is naive, 19^th Century thinking. They argue that Einstein’s theories of relativity rule it out, because clocks run at different rates depending on where they are in the Universe and how fast they are travelling relative to other observers. Actually, it’s dependent on how fast they are travelling relative to an observer following a geodesic in a gravitational field (in free fall or in orbit).

 

I’m well aware that different observers, in different parts of the Universe, see a different ‘now’, because they all see stars 100s or 1000s of light years from them, which means they see them at different ages. And, of course, some of those observers could hypothetically see some of the same stars at different ages, which means they all see a different ‘now’. And then, if they are in motion with respect to each other, that distorts the differences even further. For example, if you have 2 super novae occurring in the field of view of 2 spatially separated observers, they may well see them happening in opposite sequences. Notice that this is true even without relativistic effects.

 

So one shouldn’t be surprised if Einstein’s special theory of relativity tells us that simultaneity appears subjective, both in space and time, because it can be, even without relative motion. But obviously, this isn’t the case where causality is involved. Causality insists on a sequence in time by definition, and it has to be objective, irrespective of what observers see.

 

I like to look at the famous twin paradox, because I think it contains almost everything we need to know about the special theory of relativity. I know it’s a thought experiment, but real experiments done with atomic clocks and aeroplanes and satellites tell us it’s true. The important point is the end result – when the spacefaring twin returns, they are younger than their Earthbound twin. The same effect could be made by the twin travelling near the event horizon of a black hole, which was the premise for Chris Nolan’s movie, Interstellar (which had Kip Thorne as a consultant).

 

But here’s the thing: both twins agree on what time it is in the 4-dimensional spacetime of the Universe. So, 2 observers travelling along different paths can measure different durations of time by whatever means they have, but when they reunite, they agree on where they are in time, in the same way they agree on where they are in space. I can’t see how this is possible if there isn’t a universal ‘clock’, which is arguably the edge of time for the whole universe.

Addendum 1: Mark John Fernee, whom I reference in the main text, and has a PhD in physics, proposes a similar, if not better, argument than I do. He also gives the same explanation of entropy as an 'emergent' property through probabilities that I do in other posts. However, I expect he may not agree with me that there is a 'universal now'. This is his answer to, How did entropy become associated with time?

 

 Addendum 2: Another post by Mark John Fernee (8Aug22) gives an excellent synoptic description of the relationship between classical physics and QM, which reflects my own point-of-view.

Hannah Arendt

 I watched a movie titled, Hannah Arendt (made in 2012), which was a joint European, Israel production, and is classified as ‘biography’ on SBS (where I saw it). It’s a dramatised biography, though it contains archival footage of Adolf Eichmann’s trial in Israel. The story centres on her coverage of the trial for The New Yorker and the controversy that followed. But there are also flashbacks to a younger Hannah, when she was Martin Heidegger’s favourite student and subsequent lover.

It so happens, Philosophy Now (Issue 143, April/May 2021) also had a reasonably in-depth article on her (pp. 50-3) by Hilarius Bogbinder, a Danish born writer and translator, who studied politics and theology at Oxford and now lives in London (according to a footnote).  I re-read the article after seeing the film, and they cover much the same territory.

 

In the movie, she’s portrayed by Barbara Sukowa (who appears equally fluent in German and English) as a feisty woman, capable of holding her own with any intellectual or authority figure. Given she spent time in German occupied France helping Jews escape, before escaping to America herself, one could imagine that she would not be easily intimidated or bullied. Bogbinder describes the young Hannah:

 

Bright and precocious, Hannah [originally Johanna, but always called Hanna] was a bit of a handful. A chain-smoking, self-confident young woman, in the 1920s, she stood out from the mostly male crowd at the University of Marburg.

 

In the movie, she has a sharp mind and a sharper tongue if pushed into a corner, which happened more than once, by various forces, following her coverage of Eichmann’s trial: including Mossad, Princeton University department heads, a particularly vicious journalist from The New York Times, American Rabbis and a large proportion of the New York Jewish community. However, her students loved her.

 

According to Bogbinder, she said in a TV interview in 1964, “I am sorry, but I have to object. I don’t belong to the circle of philosophers. My profession, if you can call it that, is that of political theory.” Yet she was the first woman to teach philosophy at Princeton University. The impression one gets in the movie is that she cared very much about thinking and what I’d call ‘authentic thinking’. To me, philosophy is about argument going back to Socrates and Plato (she references that lineage at one critical point in the movie) as a bulwark against dogma and political ideology. I’ve never read any of her works, but apparently one of her most influential works was The Origins of Totalitarianism (1951) where she wrote:

 

While people in all great revolutions fight for true representation, the mob will always shout for the ‘strong man’, the ‘great leader’. For the mob hates society from which it is excluded... Plebiscites, therefore, with which modern mob leaders have obtained such excellent results, are an old concept of politicians who rely upon the mob.

 

Amazingly prescient, if one looks at recent American politics. Bogbinder makes the following observation: “Yet it is not difficult to see how many of her acute observations transcend her times, and apply to the 2020s, when demagogues denounce ‘experts’ and the ‘elites’.” This is also particularly relevant to modern-day Australian politics (for the past decade at least).

 

In this context, one can see why she might have seen herself as a ‘political theorist’, as opposed to ‘belonging to a circle of philosophers’. In one dramatic scene (in the movie), in response to a jibe from a fellow professor in a classroom full of students, she says, ‘That’s not an argument; that’s character assassination’. Maybe the experience at Princeton, following her treatment by her colleagues, made her denounce philosophy as a discipline. She also severed intellectual links with Heidegger after he became a Nazi, which would have disillusioned her.

 

A.C. Grayling, in his ambitiously titled tome, The History of Philosophy, gives her one paragraph, where he says:

 

She is an exemplar of intellect that is both penetrating and courageous. Her chief concern was to argue for the importance of political engagement as a civic responsibility, in order to defeat totalitarianism.

 

According to Grayling, she forgave Heidegger after the war. I won’t try to get into her head on that issue, after all they were once intimate.

 

Even people who have never studied philosophy or who are only vaguely aware of the horrors of the holocaust, know the name of Hannah Arendt because of the term, ‘The Banality of Evil’, which was the subtitle of her book on Eichmann, a publication of the reportage she had submitted to The New Yorker in serial form. The movie provides context for this famous utterance, especially when archival footage shows us firsthand what Eichmann said in his defence. In effect, he was a bureaucrat who was following orders, and ‘obeying the law’ of his government. Hannah Arendt’s most damning indictment against Eichmann was that he didn’t think, in fact, refused to think. The point is that she refused to paint him as a demonic monster because he wasn’t: he was an ordinary person; in effect, a ‘non-person’.

 

But, not only was she accused of ‘defending Eichmann’, which is ridiculous, but of being a ‘self-hating Jewess’, because she reported that some Jewish leaders had been complicit in the transport of Jews. When questioned on this, she simply said that it came out in the trial, so she was obliged to report it. Many in the Jewish community never forgave her for this, and her works didn’t appear in Israel until 1999, when her report, Eichmann in Jerusalem (1963), was finally published in that language.

 

Very early in the history of this blog, I wrote a post titled Evil, in response to a book written by TIME Magazine essayist, Lance Morrow. What struck me was that Morrow seemed to believe that evil required a specific personality type. I’ve never believed this. History, including recent history, is full of stories of ordinary people turning against their ‘neighbours’ based on an ingroup-outgroup dynamic. We think that people who commit atrocities in these circumstances are the exception, but the exception is the person who refuses, and in fact, saves people who have been demonised.

I think the one thing we can take from Hannah Arendt’s insight - remember she witnessed this firsthand, and was one of the ones who helped – is that evil happens when people do nothing.

 

There is relevance here to the current situation in Australia where we’ve had people in offshore detention for up to 8 years. This is inhumane, to say the least, and most of us do absolutely nothing.

The dialectic between science and philosophy

 This is a consequence of a question I answered on Quora. It was upvoted by the person who requested it, which is very rare for me (might have happened once before).

Naturally, I invoke one of my favourite metaphors. Contrary to what some scientists claim (Stephen Hawking comes to mind) philosophy is not dead, and in fact science and philosophy have a healthy relationship.

 

The original question was:

 

I see a distinction between "Philosophy" which attempts to describe and explain the world and "Science" in which theories can be proven or disproven. Under this paradigm, what areas claiming to be Science are actually Philosophy? (Requested by Michael Wayne Box.)

 

There are, in fact, 98 answers to this question, many by academics, which makes my answer seem pretty pedestrian. But that’s okay; from what I've read, I took a different approach. I’m interested in how science and philosophy interact (particularly epistemology) rather than how they are distinct, though I address that as well. My answer below:

 

 

Science as we know it today is effectively a product of Western philosophy going all the way back to Plato’s Academy and even earlier. In fact, science was better known as ‘natural philosophy’ for much of that time.

 

Science and epistemology have a close relationship, and I would argue that it is a dialectical relationship. John Wheeler provides a metaphor that I find particularly appealing:

 

We live on an island of knowledge in a sea of ignorance. As the island of knowledge expands, so does the shoreline of our ignorance.

 

I came up with this metaphor myself, independently of Wheeler, and I always saw the island of knowledge as science and the shoreline as philosophy. Seen in this light, I contend that science and philosophy have a dialectical relationship. But there is another way of looking at it, and I’d like to quote Russell:

 

Thus, to sum up our discussion of the value of philosophy; Philosophy is to be studied, not for the sake of any definite answers to its question, since no definite answers can, as a rule, be known to be true, but rather for the sake of the questions themselves; because these questions enlarge our conception of what is possible, enrich our intellectual imagination and diminish the dogmatic assurance which closes the mind against speculation; but above all because, through the greatness of the universe, which philosophy contemplates, the mind is also rendered great, and becomes capable of that union with the universe which constitutes its highest good.’ (My emphasis)

 

And this, I believe, touches on the main distinction between science and philosophy: that philosophy asks questions for which we currently don’t have answers and science actually provides answers, even if they’re provisional. And that’s why I argue there is a dialectic, because, as soon as science gives us an answer, it also gives us new questions.

 

To provide examples: Do we live in a multiverse? Will AI become sentient? Was there something before the Big Bang? What is dark matter? How did DNA evolve? All these questions are on the shoreline of our island of knowledge. They are at the boundary between philosophy and science. But that boundary changes as per Wheeler’s metaphor.

 

 

 

That’s what I wrote on Quora, but I can’t leave this subject without talking about the role of mathematics. Curiously, mathematics is also linked to philosophy via Plato and his predecessors. So I will add a comment I wrote on someone else’s post. It might be hubris on my part, but 20^th Century’s preoccupation with language defining our epistemology seems to miss the point, because the Universe speaks to us in its own language, which is mathematical. 

 

With that in mind, this is what I wrote in response to a post that concluded, Philosophy will continue as it has for the past two and a half thousand years, but we presently stand over the wreckage of a philosophical tradition four centuries in the making.

 

 

 

I believe philosophy is alive and well; it’s just had a change of clothes. You can’t divorce philosophy from science, with which it has a dialectical relationship. And that’s just concerning epistemology and ontology.

 

The mistake made in the early 20th Century was to believe mathematics is an artefact created by logic, when in fact, logic is what we use to access mathematics. Godel’s theorem and Turing’s resolution to the halting problem, demonstrate that there will always exist mathematical ‘truths’ that we can’t prove (even if we prove them there will be others). In effect, Godel ‘proved’ (ironically) that there is a difference between ‘truth’ and ‘proof’ in mathematics.

 

But there’s more: Einstein and his cohorts involved in the scientific revolution that took up the whole 20th Century, showed that mathematics lies at the heart of nature. To quote Richard Feynman:

 

Physicists cannot make a conversation in any other language. If you want to learn about nature, to appreciate nature, it is necessary to understand the language that she speaks in. She offers her information only in one form.

 

So we have an epistemological link between the natural world and mathematics. It’s not human language that defines what we call reality, but mathematics. From what I read on this subject, it seems philosophers in general still haven’t caught up with this truth.