Physical paradox
In some cases, this is the result of modern physics correctly describing the natural world in circumstances which are far outside of everyday experience.
Both of these paradoxes involve thought experiments which defy traditional common sense assumptions about time and space.
Babinet's paradox is that contrary to naïve expectations, the amount of radiation removed from a beam in the diffraction limit is equal to twice the cross-sectional area.
If the assumption that the particles in an ideal gas are indistinguishable is not appropriately taken into account, the calculated entropy is not an extensive variable as it should be.
This is a seeming violation of Newton's law of cooling but in reality it is due to non-linear effects that influence the freezing process.
A consequence of this apparent paradox is that the electric field of a point-charge can only be described in a limiting sense by a carefully constructed Dirac delta function.
A similar situation occurs in general relativity with the gravitational singularity associated with the Schwarzschild solution that describes the geometry of a black hole.
The curvature of spacetime at the singularity is infinite which is another way of stating that the theory does not describe the physical conditions at this point.
A consequence of this paradox is that the associated singularity that occurred at the supposed starting point of the universe (see Big Bang) is not adequately described by physics.
Two of these are: These thought experiments supposedly to use principles frome quantum mechanics to derive conclusions that are seemingly contradictory.
In the case of the EPR paradox, quantum entanglement appears to allow for the physical impossibility of information transmitted faster than the speed of light, violating special relativity.
Related to the EPR paradox is the phenomenon of quantum pseudo-telepathy in which parties who are prevented from communicating do manage to accomplish tasks that seem to require direct contact.
In its most crude conception, the paradox involves a person traveling back in time and murdering an ancestor who hadn't yet had a chance to procreate.
A partial resolution to this paradox is rigorously provided for by the fluctuation theorem which relies on carefully keeping track of time averaged quantities to show that from a statistical mechanics point of view, entropy is far more likely to increase than to decrease.
