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6 Electric and Magnetic Fields in Life
Electromagnetic interactions are distinguished from gravitational ones by having
both repulsive and attractive forces, while the gravitational force between localized
regions of mass and energy has always been found to be attractive. 4 If the electric
force of a distant body on a local one is measured, and then an identical second body
is put with the first, the combined body will feel exactly twice the force from the
distant one. Thus, the electric force on a body is proportional to a property carried
by the body which we call its charge. Magnetism is associated with electricity,
in that two charges moving relative to each other will each experience a force, in
addition to the electric force, called the magnetic force from the other charge. 5
Magnetic forces between charges are weaker than electric forces by a factor of
the relative speed between the charges divided by the speed of light. This makes
electric forces rather than magnetic forces a dominating factor in biochemistry and
biomolecular structures. Electromagnetism and quantum principles account for the
existence of molecules, including those involved in life. If we add in Einstein’s
gravitation theory, we can account for the origin of the elements themselves.
Our Universe was built with the ingredients to create life, even before there was
matter.
Lightning and electric sparks no doubt fascinated our prehistoric forebears.
Electricity is also evident in life: Life at the nanoscale cannot be understood
without knowing about ions, charge transfer, polarization, and intermolecular
electric forces. At the macroscopic level, we see bio-electricity at work in the
electric eel and the ability of sharks to detect weak electric fields in the surrounding
water.
The magnetic effects of lodestone and magnetized iron inspired many a child,
even to become a scientist, because non-gravitational forces acting with strength
across a visible gap are not commonly seen. Mystery evokes curiosity. But
magnetism in life is subtle. Some organisms, such as homing pigeons, can detect
the magnetic field of the Earth. Humans do not seem to have this built-in ability.
Even so, the existence of a magnetic field around the Earth has profoundly affected
our evolution through deflection of equatorial cosmic rays, shielding life from high
levels of ionizing radiation.
6.2 Ideas Behind Electricity and Magnetism
A serious study of galvanic effects in biological systems began just over 200 years
ago. After the discoveries of Oersted, Faraday, Ampere, and Gauss, linking the
4 Einstein’s gravity is always attractive.
5 The conservation of a local charge together with Einstein’s principle of relativity are sufficient
to account for the behavior of all electromagnetic effects. As Dirac showed in a 1931 paper, if
one adds quantum theory, then the discreteness of charge and the difficulty in finding an isolated
magnetic monopole can also be explained.
6 Electric and Magnetic Fields in Life
Electromagnetic interactions are distinguished from gravitational ones by having
both repulsive and attractive forces, while the gravitational force between localized
regions of mass and energy has always been found to be attractive. 4 If the electric
force of a distant body on a local one is measured, and then an identical second body
is put with the first, the combined body will feel exactly twice the force from the
distant one. Thus, the electric force on a body is proportional to a property carried
by the body which we call its charge. Magnetism is associated with electricity,
in that two charges moving relative to each other will each experience a force, in
addition to the electric force, called the magnetic force from the other charge. 5
Magnetic forces between charges are weaker than electric forces by a factor of
the relative speed between the charges divided by the speed of light. This makes
electric forces rather than magnetic forces a dominating factor in biochemistry and
biomolecular structures. Electromagnetism and quantum principles account for the
existence of molecules, including those involved in life. If we add in Einstein’s
gravitation theory, we can account for the origin of the elements themselves.
Our Universe was built with the ingredients to create life, even before there was
matter.
Lightning and electric sparks no doubt fascinated our prehistoric forebears.
Electricity is also evident in life: Life at the nanoscale cannot be understood
without knowing about ions, charge transfer, polarization, and intermolecular
electric forces. At the macroscopic level, we see bio-electricity at work in the
electric eel and the ability of sharks to detect weak electric fields in the surrounding
water.
The magnetic effects of lodestone and magnetized iron inspired many a child,
even to become a scientist, because non-gravitational forces acting with strength
across a visible gap are not commonly seen. Mystery evokes curiosity. But
magnetism in life is subtle. Some organisms, such as homing pigeons, can detect
the magnetic field of the Earth. Humans do not seem to have this built-in ability.
Even so, the existence of a magnetic field around the Earth has profoundly affected
our evolution through deflection of equatorial cosmic rays, shielding life from high
levels of ionizing radiation.
6.2 Ideas Behind Electricity and Magnetism
A serious study of galvanic effects in biological systems began just over 200 years
ago. After the discoveries of Oersted, Faraday, Ampere, and Gauss, linking the
4 Einstein’s gravity is always attractive.
5 The conservation of a local charge together with Einstein’s principle of relativity are sufficient
to account for the behavior of all electromagnetic effects. As Dirac showed in a 1931 paper, if
one adds quantum theory, then the discreteness of charge and the difficulty in finding an isolated
magnetic monopole can also be explained.