Which of the Following Particles Has Not Been Observed Experimentally

question 11

Multiple Choice

Which of the following particles has not been observed experimentally?

• A)photon
• B)graviton
• C)antiproton
• D)Z⁰ boson

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Definitions:

Rapid-eye-movement Sleep

A stage of sleep characterized by movements of the eyes, low muscle tone throughout the body, and the propensity of the sleeper to dream vividly.

Nightmares

Disturbing dreams that can cause feelings of fear, terror, or anxiety, often waking the person from sleep.

Somnambulism

Also known as sleepwalking, it is a disorder that causes people to get up and walk while in a state of sleep.

Sleepwalking

A sleep disorder leading an individual to walk or engage in other complex behaviors while still mostly asleep, often without remembering the episode later.