Massless discrete energy (hf) is stored in matter mass (m) without considering wave speed:

Author: Soumendra Nath Thakur ORCID iD: 0000-0003-1871-7803 

Dated 30-July-2023, Country: India.

Summary: Mass and energy are interconnected, but not always. Energy exists without being converted into mass, such as photons. Mass is converted into energy through nuclear reactions, fission, fusion, or radioactive decay. Energy is stored in mass without considering wave speed. Energy conversion units include Joules and electron volts. Small amounts of mass can be converted into energy through fission, fusion, or spontaneous radioactive decay.

Description: Energy exists in massless subatomic particles like photons, but not always vice versa. Electrons absorb photons without mass change. Mass converts into energy through nuclear reactions or radioactive decay. Discrete energy is stored in the mass without nuclear reactions, without considering wave speed. 1 kg m^2/s^2 energy is the derived unit of 1 joule in SI units for mass-energy conversion. The electron volt (eV) is a unit of energy. 1 eV = 1.6 * 10^-19 J. Incredible amounts of energy are converted from small amounts of mass through fission, fusion, and spontaneous radioactive decay. The mass of matter (m) contains discrete energy, similar to the atomic nucleus, electron, and electron energy. 

Conclusion: Therefore, when mass represented by (m), it is equal to (m + Em) or (m + hf) or (m + Ep), representing the cold mass of matter, the discrete energy of the mass, the discrete energy of the photon at its frequency, or the discrete energy corresponding to Planck's constant, respectively.

Recommendation: I'll provide a brief explanation and some clarifications based on the information you provided:

Mass and Energy Interconnection: The famous equation E=mc^2, proposed by Albert Einstein, shows the interconnection between mass (m) and energy (E). It states that energy (E) is equal to the mass (m) times the speed of light (c) squared. This equation implies that mass can be converted into energy and vice versa, but this conversion typically requires nuclear reactions or reactions involving extremely high energies.

Massless Subatomic Particles: Photons, which are particles of light, are indeed massless. As per the theory of relativity, they travel at the speed of light (c) and have zero rest mass.

Energy Storage in Mass: Energy can be stored in matter in various ways. For example, the energy of an electron in an atom is associated with its position and motion within the atom's electromagnetic field. This energy doesn't contribute significantly to the electron's mass, as its rest mass remains the dominant factor.

Energy Conversion Units: Joules (J) and electron volts (eV) are indeed units used to measure energy. Joules are a standard unit in the International System of Units (SI), while electron volts are commonly used in atomic and subatomic physics due to their convenience in representing small energy values.

Energy Conversion Processes: Energy can be released from matter through processes like nuclear reactions (fission and fusion) and spontaneous radioactive decay. In these processes, a small amount of mass is converted into a significant amount of energy, in accordance with Einstein's equation.

Representation of Mass and Energy: In the conclusion, you mention representations of mass, including "m + Em" for the cold mass of matter, "m + hf" for the discrete energy of the mass, and "m + Ep" for the discrete energy corresponding to Planck's constant. However, it is essential to note that these representations may require further clarification and context for precise understanding.

Overall, the connection between mass and energy is a fundamental aspect of physics, and it plays a crucial role in understanding the behavior of particles at both macroscopic and subatomic levels. The concepts you've touched upon are quite intricate and may be part of advanced physics discussions, particularly in the realm of quantum mechanics and particle physics.