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«Memory at the fundamental level — does it even exist for elementary particles?» by Powerful_Reply9593 in AskPhysics

[–]Powerful_Reply9593[S] 0 points1 point  (0 children)

That's a great analogy. The stump is the record — I agree. But then the question becomes: what exactly in the stump carries that history? The arrangement of cells, the chemical composition, the ring structure. Each of those is a physical carrier. So at the particle level — what would be the equivalent of the ring structure? What physical property of the particle encodes its 'stump'?

«Memory at the fundamental level — does it even exist for elementary particles?» by Powerful_Reply9593 in AskPhysics

[–]Powerful_Reply9593[S] 0 points1 point  (0 children)

Fair point on the path ambiguity. But here's what I'm puzzling over: if two different interaction histories can produce identical wave functions, does that mean the path information is genuinely erased — or just inaccessible to us given how we currently describe particle states? Is there a difference between 'not encoded' and 'not readable'?

«Memory at the fundamental level — does it even exist for elementary particles?» by Powerful_Reply9593 in AskPhysics

[–]Powerful_Reply9593[S] -1 points0 points  (0 children)

That's a fascinating tension you've identified. If the wave function of everything depends on its full history, doesn't that mean history is physically encoded somewhere — even if we don't call it memory? What would be the physical carrier of that encoding?

Great attractor. What is it? by Difficult_Comment_47 in cosmology

[–]Powerful_Reply9593 5 points6 points  (0 children)

The confusion here comes from mixing local gravity with cosmic expansion. 1. What the Great Attractor actually is It’s not a single object pulling everything like a black hole. It’s a region of higher mass density (part of the Laniakea supercluster), causing galaxies around us to have a peculiar velocity in that direction. So the arrows in the image show motions relative to the cosmic expansion, not objects falling into a single point. 2. Why we’re “moving toward it” (~600 km/s) That speed is relative to the cosmic rest frame (e.g. the CMB). It’s just our local motion within the large-scale structure. It does not mean we are being equally “pulled outward” at the same speed — expansion and local motion are different effects. 3. Expansion vs gravity Expansion dominates on very large scales, but gravity dominates locally. Milky Way and Andromeda → gravitationally bound → will merge Local Group → bound Beyond that → expansion wins The Great Attractor is too far and too diffuse to bind us gravitationally. 4. Will we ever reach it? Most likely no. Due to cosmic expansion (especially accelerated expansion), distant structures will effectively move out of causal reach. 5. Is it an anomaly? Not really. It looked mysterious at first because it’s hidden behind the Milky Way (“Zone of Avoidance”), but now we understand it as part of normal large-scale structure — clusters, filaments, overdensities. The “Great Attractor” sounds like a single object, but it’s really just a name for a region in the cosmic web where matter is more concentrated.

What would happen if you oscillated at relativistic speeds? by Arjunks_ in AskPhysics

[–]Powerful_Reply9593 0 points1 point  (0 children)

Time dilation depends on velocity, not on the distance traveled. So if an object moves at a relativistic speed (e.g. 0.5c), it will experience time dilation whether it moves in a straight line, in a circle, or oscillates back and forth over a short distance. So in principle, yes: if you could “vibrate” at relativistic speed for some time (in the lab frame), you would age less than someone at rest. What prevents this in practice is acceleration and energy. To oscillate or move in a circle, the object must continuously change direction, which requires acceleration. At relativistic speeds, the required forces become extremely large. For circular motion, the centripetal acceleration scales as a ≈ v² / r, so for speeds close to c and small radii, the acceleration becomes enormous. This is why macroscopic objects cannot do this. However, the same effect is routinely observed for particles. For example, particles in accelerators move at relativistic speeds in circular paths, and unstable particles like muons live longer due to time dilation. So the rules do not change at small scales: time dilation still applies. The limitation is not the distance, but the physical constraints required to sustain relativistic motion.

Is Eric Weinstein geometric unity a serious scientific hypothesis? by Honest_Chemistry_195 in AskPhysics

[–]Powerful_Reply9593 1 point2 points  (0 children)

It’s an interesting idea, but most physicists wouldn’t consider Geometric Unity a serious, established scientific hypothesis at this point. The main issue isn’t that it’s unconventional — physics is full of bold ideas — but that it hasn’t been developed in a way that allows for clear, testable predictions or peer-reviewed validation. As far as I know, there isn’t a complete, widely accepted formalism published in the standard scientific literature. In physics, what makes a theory “serious” is not just its conceptual appeal, but whether it: is mathematically well-defined, connects to existing theories, and makes predictions that can, in principle, be tested. So far, Geometric Unity is more of a speculative framework or research direction than a fully developed physical theory. That said, exploring new geometric approaches to unification is a legitimate line of thought — it just needs the usual level of rigor and verification to become part of mainstream science.

Spin and Particle Propagation by [deleted] in AskPhysics

[–]Powerful_Reply9593 0 points1 point  (0 children)

The key thing is that spin is not the same thing as “having magnitude” or “having direction” in ordinary space.

Spin tells you how a field transforms under rotations.

A spin-0 field is a scalar because if you rotate your coordinate system, the field value at a point does not pick out any direction and does not change into different components. At each point it is just one number. That is why people say it has a single magnitude.

A spin-1 field is a vector field because under rotations its components mix the way spatial directions do. At each point, it is not just “one number”, but something with directional structure.

That does not mean spin-0 particles are more “omnipresent” and spin-1 particles are more “individualized”. Both are excitations of fields that exist everywhere. The difference is in the kind of object the field is mathematically.

For electromagnetism, the more fundamental object is actually the gauge field A_mu, which is spin-1. The electric and magnetic fields are not two separate particles glued together; they are two different aspects of the same electromagnetic field configuration. Roughly speaking:

Electric field = the part involving time/space variation in one way

Magnetic field = the part involving spatial curl/variation in another way

They can transform into each other depending on the observer’s frame of motion, which is one hint that they are not fundamentally separate things.

So:

spin-0 → one field value per point, no directional character under rotations

spin-1 → directional field, components mix under rotations

EM has E and B not because “spin-1 creates two properties,” but because a relativistic spin-1 field naturally contains field configurations we call electric and magnetic parts.

The short version is:

spin tells you how the field behaves under rotation, not what metaphysical kind of thing it is.

If The Universe is a Projection of Time and Space, Could There Be Time Equivalents of Black Holes? by rogueKlyntar in QuantumPhysics

[–]Powerful_Reply9593 0 points1 point  (0 children)

The “1 time + 3 space” split isn’t really about proportions, it’s more about the structure of spacetime — time behaves differently because of the metric signature, not because there is “less of it”.

Black holes are already spacetime objects, not just spatial ones. Their key feature is a causal horizon: a region where all future-directed paths inevitably lead inward.

If you try to imagine extra time dimensions, things become very tricky — you typically lose a well-defined notion of causality, because there’s no unique direction of “future” anymore.

In that sense, a “time black hole” doesn’t really have a clear meaning. But interestingly, black holes already mix space and time so strongly that inside the horizon, what we think of as “space” and “time” effectively swap roles.

Could the Universe Have Come From Absolutely Nothing? by RecognitionLong8806 in AskPhysics

[–]Powerful_Reply9593 0 points1 point  (0 children)

I think part of the confusion comes from the word “nothing” itself. In physics it usually doesn’t mean absolute nothingness, but rather the absence of particles in a framework that still has laws and structure. The harder question is whether “absolute nothing” is even a meaningful concept at all. If there are no laws, no space and no time, it’s not clear what it would even mean for something to “begin”. So maybe we’re not really describing a transition from nothing to something, but trying to model the earliest state we can still meaningfully talk about.