Earlier in this topic, one question was put on hold: the electromagnetic, strong, and weak forces all have carrier bosons. What about gravity, the fourth force? Time to answer it.
Look for gravity on a standard-model chart, and you find nothing. Check the chart's boson column: the photon, the gluon, the W boson, the Z boson. Carriers for three forces, and no carrier for gravity.
Physicists have proposed a carrier for gravity, and even named it: the graviton. But the graviton differs from the other carriers in one decisive way: no experiment has ever detected one.
So the standard model stays scoped to three forces, and gravity sits outside it.
A student searches a standard-model chart for gravity's carrier boson. What do they find?
The chart lists carriers for the electromagnetic, strong, and weak forces.
The standard model does not describe gravity.
No carrier for gravity appears on the chart.
What is the graviton?
Physicists proposed a carrier particle for gravity and named it the graviton.
No experiment has ever detected one.
The graviton is gravity's proposed carrier — proposed, and never detected.
The standard model describes three of the four fundamental forces. Which force is left out?
Which statement about the graviton is correct?
How many of the four fundamental forces have carrier bosons on a standard-model chart?
Which three forces does the standard model describe?
What is the name of gravity's proposed carrier boson?
Why is the graviton not shown on a standard-model chart?