Well, if only we had these very intense fields at hand. There's yet no observation of this socalled Schwinger mechanism :-(.mfb said:
Not yet, but the lasers are making progress towards it.vanhees71 said:
Yes! This has a long history in heavy-ion collisions. As far as I know, so far there's also no (clear) evidence for the Schwinger effect there either. It's already tough to get the "normal dileptons" (which are very interesting in themselves, because they provide the most direct probe for in-medium effects of hadrons in the fireball created in heavy-ion collisions).mfb said:
But magnetic detectors such as these contain charges.BvU said:
Depends on what we count as detection. The mass of a singly ionized helium atom, the mass of an electron, and the mass of doubly ionized helium can all be measured to better than 10 eV. The first one is the sum of the other two minus 54 eV (the second ionization energy of helium). A +54 eV contribution from kinetic energy and a -109 eV contribution from the electric field. That contribution is measurable.hilbert2 said:
Yes, a field can exist without any charge present. Fields are physical phenomena that exist in space and are not dependent on the presence of charge. Examples of fields include gravitational fields, electric fields, and magnetic fields.
There are several ways to detect the presence of a field without any charge. One way is to use a field detector or sensor, such as a magnetometer or an electric field probe. These devices can measure the strength and direction of a field and can indicate its presence. Another way is to observe the effects of the field on other objects, such as the movement of a compass needle in a magnetic field.
Fields and charges are closely related, as fields are created by the presence of charges. Charges have an electric charge, which can create an electric field, and a mass, which can create a gravitational field. The presence and movement of charges can also affect the strength and direction of a field.
No, not all fields are invisible. Some fields, such as electric and magnetic fields, are not visible to the naked eye, but they can be detected using specialized equipment. Other fields, such as gravitational fields, are not directly visible, but their effects can be observed in the movement of objects.
Fields cannot be created or destroyed, but they can be generated or altered by the presence and movement of charges. For example, an electric field can be generated by separating positive and negative charges, and a magnetic field can be created by moving electric charges. Fields can also be affected by other fields, such as the way gravitational fields interact with each other.