Comment by hansen | Hacker News Reader

Comment by hansen | Hacker News Reader

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> there is enough experimental evidence that is anomalous to the theories

Huh? I have more the impression that Λ-CDM & SM are working just too damn good. I’m not aware of any observation that hints that we need something completely different than GR & local QFT.

But “settled” and “well established” doesn’t mean that humans will never find a more fundamental theory. Classical mechanics is settled, well established and correct as it was in Newtons times. Now we just better understand its limits and when to use different models.

GR, QM & QFT are correct and won’t go away. At some point in the future we will have a better understanding of their limits too. But that won’t make them wrong.

> The fact that we don't know and that our current suite of theories is incomplete and hence could very well be wrong in both minor and major ways should be driving us onward into understanding the universe around us. It really is not a problem if we don't understand. It should mean that we strive to learn more.

I’m not objecting exploring new speculative models. I’m worried about presenting highly speculative ideas as facts or probable solutions to the public. A lot of the pop-sci articles you read these days are very misleading. And IMHO Rovelli, Green, Susskind, Smolin and the like aren’t doing anyone a favor with their pop-sci books.

Don't ever use the word "correct" for any theory we use. If you actually read and understand the basis for any theory or model in use, you will come to see that each is capable of giving "close enough" predictions, but none will give perfect predictions and that there are always anomalous data that these theories and models cannot explain.

Be pragmatic and keep in mind that wonderful phrase - "All theories are wrong, but some are useful."

The problem I see is that it is a common activity to present "settled" and "well established" as fact. Often without ever highlighting the anomalies that have been found and that we only have a "belief" that it is useful.

One of the best examples is the case for "dark matter". It has never been established in any way that such "dark matter" exists. It only arises because the observed motion within galaxies does not accord with "settled" and "well established" theory. So to keep this "settled" and "well established" theory, some additional "theoretical entity" has been added to allow the observations to fit the "settled" and "well established" theory.

Now, that addition of a new "theoretical entity" is, in itself, not a problem. What becomes the problem is when every experiment fails to show that "theoretical entity". At this point, one should be saying that mayhaps the "settled" and "well established" theory is not so settled and not so well established. Mayhaps there is a problem that we then need to be looking at.

My point here is that we do not, in fact, have any real or clear understanding of the universe about us. We have models and theories that work within a limited range but they are not global. The simplest of these is that "chestnut" between general relativity and quantum mechanics (the large and the small). The funny thing here is that we can make devices that are macroscopic which exhibit, under certain circumstances, the effects we see at microscopic levels. Why? What is happening here? What are we missing in this crossover realm? Why do we see things in the laboratory and see similar things at extra-solar distances, yet the explanations of these effects do not accord with the "settled" and "well established" theory we use at those massive sizes?

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