Is the Mass Defect in Heavy Nuclei Well Supported by Scientific Evidence?

[granpa]

how sure are we that heavy nuclei are less massive than the sum of their constituent particles? the masses of atoms are determined by sending their ions through magnetic fields and measuring how much they are deflected. how do we know that heavy nuclei don't simply produce, at any given velocity, slightly stronger magnetic fields than lighter nuclei?

 

[malawi_glenn]

The nuclei bend in Magnetic fields due to their own charge. The magnetic field is external, the only thing you are measuring of the nuclei is their charge vs. mass ratio.

So there is not a magnetic field beeing produced by the nucleus.. only electric charge, which electric field is additative.

There was a crackpot here almost a year ago who claimed that the other protons in the nuclei whould sheild the charge from the protons inside, hence resulting in a smaller net charge than the sum of the constituent protons... but as he didn't know, equal charges do not screen...

 

[sir-pinski]

The concept of mass defect, or the difference between the mass of a nucleus and the sum of its constituent particles, has been extensively studied and verified through various experiments and theoretical calculations. Therefore, we can be fairly confident that heavy nuclei are indeed less massive than the sum of their constituent particles.

One of the main pieces of evidence for this is the observation of nuclear binding energy. This is the energy that holds the nucleus together and is responsible for the mass defect. The existence of binding energy has been confirmed through multiple experiments, such as nuclear reactions and nuclear decay.

Additionally, the masses of atoms are not solely determined by their deflection in magnetic fields. Other methods, such as mass spectrometry and nuclear reactions, are also used to measure the masses of atoms. These methods have been extensively tested and validated, providing further evidence for the existence of mass defect in heavy nuclei.

Furthermore, the idea that heavy nuclei could simply produce stronger magnetic fields at any given velocity has been considered and ruled out by numerous experiments and theoretical calculations. The laws of physics and the behavior of particles at the nuclear level have been extensively studied and are well understood, making it highly unlikely that such a scenario could occur.

In summary, while it is always important to question and test scientific theories, the evidence supporting the existence of mass defect in heavy nuclei is strong and has been extensively studied and validated. Therefore, we can be confident in the understanding that heavy nuclei are indeed less massive than the sum of their constituent particles.