There is an entire literature concerning the "structure of matter", ranging from the "electrical structure" in the early 20th century, to the more recent "quark structure of matter", introduced today with the remark: Understanding the quark structure of matter has been one of the most important advances in contemporary physics.[further explanation needed] In this connection, physicists speak of matter fields, and speak of particles as "quantum excitations of a mode of the matter field". And here is a quote from de Sabbata and Gasperini: "With the word "matter" we denote, in this context, the sources of the interactions, that is spinor fields (like quarks and leptons), which are believed to be the fundamental components of matter, or scalar fields, like the Higgs particles, which are used to introduced mass in a gauge theory (and that, however, could be composed of more fundamental fermion fields)."[further explanation needed]

When did de Sabbata and Gasperini write?

I'm not sure.

What theory came after the quark structure of matter?

I'm not sure.

Understanding electrical structure has lead to important advances in what field?

I'm not sure.

Who described particles as quantum excitations?

I'm not sure.

What theory uses spinor fields?

I'm not sure.


In the late 19th century with the discovery of the electron, and in the early 20th century, with the discovery of the atomic nucleus, and the birth of particle physics, matter was seen as made up of electrons, protons and neutrons interacting to form atoms. Today, we know that even protons and neutrons are not indivisible, they can be divided into quarks, while electrons are part of a particle family called leptons. Both quarks and leptons are elementary particles, and are currently seen as being the fundamental constituents of matter.

What field of physics began in the 19th century?

I'm not sure.

What do atoms form?

I'm not sure.

What are quarks divided into?

I'm not sure.

Leptons are made up of what?

I'm not sure.

We now know that quarks and leptons are not what?

I'm not sure.


These quarks and leptons interact through four fundamental forces: gravity, electromagnetism, weak interactions, and strong interactions. The Standard Model of particle physics is currently the best explanation for all of physics, but despite decades of efforts, gravity cannot yet be accounted for at the quantum level; it is only described by classical physics (see quantum gravity and graviton). Interactions between quarks and leptons are the result of an exchange of force-carrying particles (such as photons) between quarks and leptons. The force-carrying particles are not themselves building blocks. As one consequence, mass and energy (which cannot be created or destroyed) cannot always be related to matter (which can be created out of non-matter particles such as photons, or even out of pure energy, such as kinetic energy). Force carriers are usually not considered matter: the carriers of the electric force (photons) possess energy (see Planck relation) and the carriers of the weak force (W and Z bosons) are massive, but neither are considered matter either. However, while these particles are not considered matter, they do contribute to the total mass of atoms, subatomic particles, and all systems that contain them.

How many quarks and leptons are there?

I'm not sure.

What model satisfactorily explains gravity?

I'm not sure.

Interactions between quarks and leptons are the exchange of what?

I'm not sure.

Mass and energy can always be compared to what?

I'm not sure.

What relation explains the carriers of the electric force?

I'm not sure.


The term "matter" is used throughout physics in a bewildering variety of contexts: for example, one refers to "condensed matter physics", "elementary matter", "partonic" matter, "dark" matter, "anti"-matter, "strange" matter, and "nuclear" matter. In discussions of matter and antimatter, normal matter has been referred to by Alfvén as koinomatter (Gk. common matter). It is fair to say that in physics, there is no broad consensus as to a general definition of matter, and the term "matter" usually is used in conjunction with a specifying modifier.

Physics has broadly agreed on the definition of what?

I'm not sure.

Who coined the term partonic matter?

I'm not sure.

What is another name for anti-matter?

I'm not sure.

Matter usually does not need to be used in conjunction with what?

I'm not sure.

What field of study has a variety of unusual contexts?

I'm not sure.