Modern physics holds that light is both a particle and a wave. This contradicts the Law of Identity. :dough:
How does one (qua the Objectivist metaphysics) resolve this conundrum? 
Metaphysics doesnât enter into it. Itâs Physics, leave it to the Physicists.
Modern physics holds that light is both a particle and a wave. This contradicts the Law of Identity. :dough:
How does one (qua the Objectivist metaphysics) resolve this conundrum?
As a matter on fact not only light but ALL so called particles and waves have particle and wave properties.
Te problem is not with the law of identity, it is a problem of physics epistemolegy (sorry for my spelling if it is not right). Physics objects were supposed to fall in one of the two categories and now we know that âparticleâ and âwaveâ are non contradictory concepts, and that an object does have both properties*
*although following the uncertainly principle
TheEgoist is right, it is up to the physicists to straighten out. You may know the law of identity but that does not entitle you to sit back in an overstuffed chair in your personal library with a cigar and brandy snifter and solve the worldâs problems.
Two concepts that were once thought to refer to different things (particle, wave), now turn out to overlap in terms of their referents (e.g. light). Their usefulness for describing how the universe works has been exhausted - the context in which those concepts are useful has been delimited. New concepts will have to be created to better understand the full range of observations.
The appearance of a contradiction is simply a guide for furthering oneâs understanding: since contradictions canât exist, I will have to determine exactly what about my current conceptual understanding is presenting the appearance of a contradiction.
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Cherring metaphysics is at the foundation of all knowledge. Philosophy has the veto on any special science in regards to invalid use of concepts such as incommensurate characteristics etc. Anyway Bohm does not have this contradiction from what I understand. You are in agreement with Peikoff and Harriman on this issue by the way.
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The simple way to put it is that light is a wave and a particle the way a man is blond and tall. Properly defined, wave and particle arenât contradictory characteristics.
Two concepts that were once thought to refer to different things (particle, wave), now turn out to overlap in terms of their referents (e.g. light). Their usefulness for describing how the universe works has been exhausted - the context in which those concepts are useful has been delimited.
Exactly. Just to expand on this point, for instance the wave theory of light came about when scientists found similarities between light and sound, that supported a wave model to represent light (an analogy to sound). That analogy is great when it helps people easily understand and communicate the properties which are common to light and sound, but stopped being useful when it was over extended, to cover properties of sound waves which were not in fact observed characteristics of light (like a medium for the waves to propagate in - scientists who over extended the analogy came up with the notion of âetherâ, and spent time looking for it, even though there is no evidence, only the logical error of over extending an analogy, to suggest âetherâ exists).
So, if we define a wave as something that has the properties of sound (including the property that it propagates in a medium), it is not correct to say light " is a" wave. It " is like a" wave, in some useful respects.
Or, we can define âwaveâ to refer to only those properties which light and sound have in common, in which case it is correct to say light is a wave. This second definition is in fact the definition of âwaveâ in Physics: âElectromagnetic radiation (often abbreviated E-M radiation or EMR) is a phenomenon that takes the form of self-propagating waves in a vacuum or in matter. Light is EMRâ (Wikipedia)
The only reason why anyone would talk about contradictions, or a paradox, in Physics is because they are confusing the proper role of concepts, and using them as primaries instead of what they are: tools to aid our representation of reality. Einstein had no such misconceptions, his wave-particle theory of light is perfectly logical and contains no contradictions. Light (and everything else) can be described both by particles and waves. Neither describes things fully, and the two descriptions donât contradict, they complement each other.
For particle physicists, the word âparticleâ labels a vastly different concept than the classical concept âparticleâ.
For example, in the context of Quantum Field Theory, a particle is an elementary excitation of an underlying quantum field. Within QED, the photon has definite energy. To have definite energy, a photon is localized in momentum space but not position space.
In classical physics, a particle is localized in both position space and momentum space. But in quantum mechanics and quantum field theory, there is no particle state that is localized in both spaces (although there are states that minimize the product of the âspreadsâ in both spaces). And, since the energy eigenstates of a free quantum field are discrete multiples of some basic quanta of momentum/energy, those quanta are called âparticlesâ. Do not confuse that concept with the classical concept of a spatially localized entity.
Consider a guitar string vibrating back and forth. Now, imagine that the amplitude of the vibration can only take certain discrete values and that those values are integer multiples of some fundamental vibrational quanta (particle) called a âphononâ. For example, letâs say the amplitude was 9 times the fundamental amplitude. Physicists would say that 9 phonons (âparticlesâ of vibration) are present. But, âwhereâ are the particles of vibration? Kind of hard to answer that.
It is always up to people to resolve their contradictions in their theories. No science can disprove the law of identity, because the the idea of proof is relient on proof.
If I invented a machine that took measurements and got contradicting results, I would be someone who made a bad measurement device, not a someone who revolutionized metaphysics.
Thanks everyone for their comments so far. Itâs been very enlightening! :worry:
Itâs seems apparent to me that i am just ignorant of physics. 
Thanks for every-bodies help. 
It is always up to people to resolve their contradictions in their theories. No science can disprove the law of identity, because the the idea of proof is relient on proof.
If I invented a machine that took measurements and got contradicting results, I would be someone who made a bad measurement device, not a someone who revolutionized metaphysics.
They donât get contradicting results, that is the whole point. Take the double-slit experiment. If you set up some type of detector which interacts with the particles prior to them reaching the screen, you get two lines on your photographic plate. If you have no such detector, then you get an interference pattern exactly as if it was a wave moving through both slits at once. You donât get both two lines and an interference pattern or something like that, ever. Scientists have worked on explaining quantum mechanics for decades, and the commonly accepted explanation is something called decoherence, which can in broad strokes be described like this: the probabilistic nature of particles (in terms of their behavior) is leaked into the environment when measured (for example, we now know the position of the particle, but now the detector could be in a number of very slightly different states). This is why we see dramatic quantum effects when we manipulate subatomic particles but nothing on the macro-scale (the particles are tiny compared to the enormous systems measuring them, so their localization has no important effect on the macro-scale system). If you calculate the de Broglie wavelength of a baseball, itâs something like 10^-24 meters (size of a proton, say). That doesnât seem like a contradictory position. And then of course there is the many-worlds interpretation and the Bohm interpretation, which have no such uncertainty within them at all, and every particle is always localized to a point and a particular momentum.
Really, if we are talking about wave-particle duality, all that we are saying is that things at the subatomic level behave in a manner that is like a wave in some cases and like a particle in others. It all depends on context. It isnât wrong to say that something can behave in different ways in different situations, it is an expression of the nature of causality and thus the law of identity. Now, perhaps you have a problem with things behaving in a fundamentally undeterministic manner (that is, one can never know with certainty where a particle will end up, that sort of thing), but I still donât see that as a conflict with the law of identity.
Law of identify comes first:
If you assume you can look for any answer upon that specific physics â therefore it is right and characteristic of âparticleâ does not contradict the characteristic of âwaveâ.
As it does, something cannot be both, none or the middle of wave and particle, that specific modern physics is not proper to the law of identify and and you donât have to refer to it at all.
T.R.
They donât get contradicting results, that is the whole point. Take the double-slit experiment. If you set up some type of detector which interacts with the particles prior to them reaching the screen, you get two lines on your photographic plate. If you have no such detector, then you get an interference pattern exactly as if it was a wave moving through both slits at once. You donât get both two lines and an interference pattern or something like that, ever.
Of course they get contradictory results, otherwise it would not have been necessary to create the notion of a âwave-particle dualityâ. The contradiction was the appearance that a particle went through two slits at the same time. The contradiction was resolved by revising the notion of a particle to include wave-like properties.
Of course they get contradictory results, otherwise it would not have been necessary to create the notion of a âwave-particle dualityâ. The contradiction was the appearance that a particle went through two slits at the same time. The contradiction was resolved by revising the notion of a particle to include wave-like properties.
Iâm not convinced that the notion of a particle that includes wave-like properties is coherent.
Also, the classical notion of âparticleâ (an entity with definite spatial localization) survives in Bohmian Mechanics so one does not have to accept the notion of a particle with wave-like properties to get predictions that correspond with experimental results. Rather, one must instead accept explicit non-locality.
Iâm not convinced that the notion of a particle that includes wave-like properties is coherent.
Also, the classical notion of âparticleâ (an entity with definite spatial localization) survives in Bohmian Mechanics so one does not have to accept the notion of a particle with wave-like properties to get predictions that correspond with experimental results. Rather, one must instead accept explicit non-locality.
Yes
Thanks everyone for their comments so far. Itâs been very enlightening! :worry:
Itâs seems apparent to me that i am just ignorant of physics.
Thanks for every-bodies help.
Donât feel too bad. The categories werenât presented to you properly.
Popular science books are usually written by non-scientists who donât know history of science, let alone what the abstractions refer to in reality.
Feynman rescues physics from their absurdity in QED: A Strange Theory of Light and Matter.
Light exists non-contradictorily, separate from human understanding. Because physicists have a contradicting definition of it and contradictions cannot exist, they must change their definitions to eliminate the contradiction.
Light exists non-contradictorily, separate from human understanding. Because physicists have a contradicting definition of it and contradictions cannot exist, they must change their definitions to eliminate the contradiction.
Part of that will involve integrating a wide variety of facts.
This is the only physics discussion on ObjectivismOnline that I have ever seen go right! Light does weird things in some experiments as well as any particle, it doesnât mean that the whole wave/particle thing is all wrong, it just means that neither is completely correct, and that we donât know exactly what is going on! Iâve read that this phenomenon has been observed in molecules as large as buckey balls! (soccer ball of carbon atoms)
This is the only physics discussion on ObjectivismOnline that I have ever seen go right! Light does weird things in some experiments as well as any particle, it doesnât mean that the whole wave/particle thing is all wrong, it just means that neither is completely correct, and that we donât know exactly what is going on! Iâve read that this phenomenon has been observed in molecules as large as buckey balls! (soccer ball of carbon atoms)
Weâre on the verge of a new concept as revolutionary as Faradayâs concept of âfieldâ was.