The key difference between matter and antimatter is that matter and antimatter have opposite electrical charges.
Matter dominates our universe. Things such as planets, stars, and people are made of mater, but there are also dark matter and dark energy we cannot detect easily. However, scientists have found that matter comes in pairs. That means; all matter has its own antimatter, which has identical properties except for the electrical charge. For example, a proton has a positive charge, while an antiproton has a negative charge. But, they have the same mass and other properties.
CONTENTS
1. Overview and Key Difference
2. What is Matter
3. What is Antimatter
4. Side by Side Comparison – Matter vs Antimatter in Tabular Form
5. Summary
What is Matter?
Matter is any substance that has a mass and a volume. The matter is made up of atoms. An atom is made up of subatomic particles. However, we usually consider atom as the basic unit of matter. The term matter does not include massless particles such as photons. Moreover, energy phenomena such as light and sound are not considered as matter. Matter can exist in different phases: solid phase, liquid phase, and gas phase. However, another phase of matter is possible; we name it as the plasma state. The plasma state contains atoms, ions and free electrons that are removed from atoms to form the ions.
An atom contains an atomic nucleus, which contains protons and neutrons along with some other subatomic particles, surrounded by a cloud of electrons. However, modern quantum physics states that an atom can act as both a particle and as a wave; we name this as wave-particle duality.
Figure 01: Quark Structure of a Proton
In addition to using atoms, or protons, neutrons and electrons, we can define matter using leptons and quarks as well. These are elementary particles of matter. According to this definition, ordinary matter is anything that is composed of leptons and quarks. Therefore, the matter is anything that does not contain antileptons and antiquarks. Leptons and quarks combine to form atoms. Atoms combine to form molecules. Atoms and molecules can be named as matter. However, electrons are a type of leptons and protons and neutrons are made of quark particles. Therefore, all these definitions lead to the idea that matter is anything having a mass and a volume and not antimatter.
What is Antimatter?
Antimatter is the matter containing antiparticles that contribute to the formation of matter. Therefore, antimatter is the opposite of matter. For example, proton and antiproton are a pair of matter and antimatter, respectively. The matter and antimatter pairs have the same mass but opposite electrical charges. They have some differences in quantum properties as well. e.g. a proton is positively charged while an antiproton has a negative charge.
Figure 02: A Cloud Chamber Photograph of a Positron
A collision between matter and antimatter can lead to mutual annihilation. It means both matter and antimatter convert into other particles having equal energies. The annihilation can give rise to intense photons such as gamma rays, neutrinos, and some other particle-antiparticle pairs. However, the majority of the energy released from annihilation is in the form of ionizing radiation.
Similar to matter, antimatter particles can bind with each to form antimatter. For instance, a positron is the antiparticle of the electron, while antiproton is the antiparticle of a proton; these two antiparticles can bind to form an antihydrogen atom. We can denote the antimatter using a bar sign over the particle’s symbol in order to distinguish it from matter.
What is the Difference Between Matter and Antimatter?
The key difference between matter and antimatter is that matter and antimatter have opposite electrical charges. Antimatter is basically the opposite of matter, but they have identical properties other than electrical charge.
Below infographic summarizes the difference between matter and antimatter.
Summary – Matter vs Antimatter
Antimatter is the opposite of matter, but they have identical properties in addition to the electrical charge. The key difference between matter and antimatter is that matter and antimatter have opposite electrical charges.
Reference:
1. “Matter.” Wikipedia, Wikimedia Foundation, 10 Dec. 2019, Available here.
Image Courtesy:
1. “Proton quark structure” By Jacek rybak – Own work (CC BY-SA 4.0) via Commons Wikimedia
By Carl D. Anderson (1905–1991) – Anderson, Carl D. (1933). “The Positive Electron”. Physical Review 43 (6): 491–494. DOI:10.1103/PhysRev.43.491 (Public Domain) via Commons Wikimedia