## Physics Questions People Ask Fermilab

Deeper connection between Higgs particle and gravity?

Dear Fermi Lab,
Matter has inertial when it we try to accelerate it through space. This inertial mass is the same as mass that gravity acts on. This implies a deep connection connection between matter and space. My understanding is that that is what Einstein's General Relativity describes. Also, my understanding is that mass is theorized to be related to (or caused by) the Higg particle(s). The effort it takes to increase an object's speed is because of the Higgs particle(s) interacting with the matter in the object. Can you explain this some more? .... and does this mean (because of the equivalence of intertial mass and gravitational mass) that there is a deeper connection between the Higg particle(s) and gravity? Thank you for the work you are doing in trying to give us all a deeper understanding of nature. Sincerely,

Scott Pennington

Hi Scott,

I would start with your last statement. It is very nice that you admire our work so much. It is really nice to know, that there is a need for answers to those deep and fundamental questions we are studying here at Fermilab. While there are curious people as yourself, we will try to do our best to provide you with the most precise answers. But now back to the actual physics.

When you say "Matter has inertial when it we try to accelerate it through space. This inertial mass is the same as mass that gravity acts on. This implies a deep connection connection between matter and space. My understanding is that that is what Einstein's General Relativity describes.", you are very much right, but for completeness, I would add few lines to make this a little bit more transparent. When Einstein's General Relativity talks about deep connections between matter and space, the following is meant. MATTER FORMS THE SHAPE OF THE SPACETIME, AND THE SPACE TIME TELLS MATTER HOW TO MOVE! In other words, if you have a certain distribution of matter, it shapes the space time. This is done through Einstein's equations. On the other hand, the geometry of the space time dictates how matter moves in it. This is again described by Einstein's equations. These two phenomena are tight very closely, one cannot exist without the other one. And this is what the deep connection between space and matter means.

Further you say: " Also, my understanding is that mass is theorized to be related to (or caused by) the Higg particle(s). The effort it takes to increase an object's speed is because of the Higgs particle(s) interacting with the matter in the object." The first statement is perfectly true, however I would not agree with the second one. Let us see how this Higgs issue works. For a moment, we are going to leave general relativity and we jump to the framework of the quantum world. Everything starts with a theory, called The Standard Model. This is a very very successful theory, which describes interactions of particles. This theory is based on certain principles that physicists think to be important, such as various symmetries. For example a symmetry called gauge symmetry. For now it is not important what exactly this means, important is that by requiring such a symmetry, one was able to come out with an elegant, compact and simple theory of elementary particles. This theory however had a bug, it predicted that the electrons, muons, quarks, ... ( all the spin 1/2 particles) and the intermediate bosons ( W's, Z) as we see them today, were MASSLESS.

The conclusion was that the symmetry that physicists thought to be exact, must be broken in the world we live in. They started to think, how this could happen, and one of the solution was to introduce a new particle, called the Higgs boson. There are many other suggestions in the air, and one of our goals here at Fermilab is to address these questions and to answer who is right and who is wrong. By introducing the Higgs boson, the above mentioned problem disappeared, the particles were massive as they should be, and they obey the laws of gravity. BUT THE EFFORT YOU NEED TO MAKE TO ACCELERATE A PARTICLE IS NOT ORIGINATED in the interaction of the Higgs with the matter.Nobody on Earth has come out with a theory, which would unify the quantum and the gravity worlds!! This is still under development, and many theorists are working on this issue. So, please wait a little bit, and maybe soon, in our life time we will know the truth.

Hope this helped at least a little bit,
bye Arnold

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