May 18, 2025 05:10 PM
Can you take religion out of cosmology?
https://iai.tv/articles/the-big-bang-can..._auid=2020
INTRO: We tend to think our scientific and cosmological theories are devoid of religious thinking. But, it was actually a priest, George Lemaître, who originally proposed the Big Bang theory. In this extract from their new book, Battle of the Big Bang: The New Tales of Our Cosmic Origins, argue belief in the Big Bang as a singularity and the beginning of space and time, is just that, a belief. We have no evidence that can prove this version of the Big Bang. Afshordi and Halper argue some of our cosmological models have taken on creation myth status and attract very religious styles of thinking in the scientific community.
EXCERPTS: [...] But in the theoretical physics community, you may be exiled into the wilderness if you entertain the idea of faster-than-light signals (Magueijo), time loops (Gott), violating null energy conditions (Steinhardt and Ijjas), modified gravity to replace dark matter (Moffat and Bekenstein), or basically anything other than inflation and string theory. While exile may be better than being burnt at the stake, consider that if anonymous reviewers decide your starting assumptions are “not well- motivated,” “plausible,” or “consistent with known physical principles,” you cannot get your papers published, get funding, or hire students.
But perhaps we shouldn’t take this analogy too far. Phil thinks I’m being too pessimistic. He pointed out that the rebels he interviewed for this book seem to be doing fine, their anonymous reviewers and employers have been more open minded, their papers get published, and they have good academic jobs. Vive la résistance! But I’m not fully persuaded. Perhaps he is being too optimistic? We should also be wary of survivorship bias, the idea that the famous faces and voices we get to read and hear in top journals and TV interviews don’t necessarily represent the struggles of the broader community. So, take this caution as a warning about what can and (speaking from the trenches) all too often does go wrong.
[...] Again, almost no cosmologists believe in the singularity; it’s an artifact of pushing Einstein’s theory of gravity beyond its limits. The singularity marks a state of infinite density, curvature, temperature, and pressure and so should be denied, not embraced, by Craig—who also tells us infinity is impossible. I’m also skeptical that the notion of causality can be applied at a fundamental level. In my own models where, for example, there are multiple dimensions of time, time loops, or no time at all, causality may not be an appropriate concept. It’s plausible that our perception of cause and effect, like the wetness of water, is an emergent concept, absent from fundamental physics but present in our day-to-day lives. So Big Bang cosmology does not show that the universe had a beginning; and even if it did, we have no right to demand that such a beginning must have had a cause.
[...] That argument is related to what puzzled Roger Penrose, namely why was the entropy so low at the Big Bang when high entropy seems more probable than low entropy? But a low-entropy state is improbable anywhere on the timeline of the universe, whether it happens to be at the start of a universe with a beginning or in the middle of one without. So, the puzzle does not provide evidence for one class of models over another.
My own point of view is somewhat more nuanced: that growing entropy, like the sunrise and sunset, is an observer-dependent effect. Simply put, the second law of thermodynamics says that if you start from a special state, you are likely to evolve to more and more random states, but the state that I find special may be different from yours: a boring day in my life may be the day that you win the lottery. One can describe a deck of cards being shuffled as a process that increases entropy. But in some sense the original order is just as unlikely as any other sequence, and it’s our arbitrary choice to call the starting state one of low entropy. Similarly, it’s not that the entropy was low at the Big Bang; that’s just how it appears to us... (MORE - missing details)
https://iai.tv/articles/the-big-bang-can..._auid=2020
INTRO: We tend to think our scientific and cosmological theories are devoid of religious thinking. But, it was actually a priest, George Lemaître, who originally proposed the Big Bang theory. In this extract from their new book, Battle of the Big Bang: The New Tales of Our Cosmic Origins, argue belief in the Big Bang as a singularity and the beginning of space and time, is just that, a belief. We have no evidence that can prove this version of the Big Bang. Afshordi and Halper argue some of our cosmological models have taken on creation myth status and attract very religious styles of thinking in the scientific community.
EXCERPTS: [...] But in the theoretical physics community, you may be exiled into the wilderness if you entertain the idea of faster-than-light signals (Magueijo), time loops (Gott), violating null energy conditions (Steinhardt and Ijjas), modified gravity to replace dark matter (Moffat and Bekenstein), or basically anything other than inflation and string theory. While exile may be better than being burnt at the stake, consider that if anonymous reviewers decide your starting assumptions are “not well- motivated,” “plausible,” or “consistent with known physical principles,” you cannot get your papers published, get funding, or hire students.
But perhaps we shouldn’t take this analogy too far. Phil thinks I’m being too pessimistic. He pointed out that the rebels he interviewed for this book seem to be doing fine, their anonymous reviewers and employers have been more open minded, their papers get published, and they have good academic jobs. Vive la résistance! But I’m not fully persuaded. Perhaps he is being too optimistic? We should also be wary of survivorship bias, the idea that the famous faces and voices we get to read and hear in top journals and TV interviews don’t necessarily represent the struggles of the broader community. So, take this caution as a warning about what can and (speaking from the trenches) all too often does go wrong.
[...] Again, almost no cosmologists believe in the singularity; it’s an artifact of pushing Einstein’s theory of gravity beyond its limits. The singularity marks a state of infinite density, curvature, temperature, and pressure and so should be denied, not embraced, by Craig—who also tells us infinity is impossible. I’m also skeptical that the notion of causality can be applied at a fundamental level. In my own models where, for example, there are multiple dimensions of time, time loops, or no time at all, causality may not be an appropriate concept. It’s plausible that our perception of cause and effect, like the wetness of water, is an emergent concept, absent from fundamental physics but present in our day-to-day lives. So Big Bang cosmology does not show that the universe had a beginning; and even if it did, we have no right to demand that such a beginning must have had a cause.
[...] That argument is related to what puzzled Roger Penrose, namely why was the entropy so low at the Big Bang when high entropy seems more probable than low entropy? But a low-entropy state is improbable anywhere on the timeline of the universe, whether it happens to be at the start of a universe with a beginning or in the middle of one without. So, the puzzle does not provide evidence for one class of models over another.
My own point of view is somewhat more nuanced: that growing entropy, like the sunrise and sunset, is an observer-dependent effect. Simply put, the second law of thermodynamics says that if you start from a special state, you are likely to evolve to more and more random states, but the state that I find special may be different from yours: a boring day in my life may be the day that you win the lottery. One can describe a deck of cards being shuffled as a process that increases entropy. But in some sense the original order is just as unlikely as any other sequence, and it’s our arbitrary choice to call the starting state one of low entropy. Similarly, it’s not that the entropy was low at the Big Bang; that’s just how it appears to us... (MORE - missing details)
