Subject: Can Dark Energy be Negative ?

The hyperbola describing the energy-momentum invariance of Tachyons passes 
into the region of negative energy has been held to imply the existence of an 
infinite source of energy. According the curve for Tachyons, they can have 
(mathematical) negative energy. 
Can Tachyons really own negative energy ?
We know that there is dark energy that permeates all of space and tends to 
increase the rate of expansion of the universe. This energy has a negative 
pressure, is there a possibility that this energy in comparement with the 
gravitational energy, can also own a negative value ? Why ? Is this an 
improper question ? Why ?
A scientist claimed that Negative energy Tachyons (Neutrinos with negative 
energies) were coming out from a black hole. Another scientists Kabat and 
Princeton University’s G. Lifschytz suggested that particles spit out tachyons 
as they merge with a black hole.
Again, A. Sen, G. Gibbons und Xin-zhou Li claimed that tachyons were 
antigravitational pressure waves, a concept which is able to explain the 
superluminal expansion of the Universe. According the given information, can 
we ask these questions :

a- Is Dark energy made of Tachyons ? Can you give a definitive answer, as yes 
or no, with reasons ?

b- Does particles spit out tachyons as they merge with a black hole ? Can you 
give a definitive answer, as yes or no, with reasons ?

c- According to K. Meyl, is there a possibility that these Tachyons (tachyonic 
neutrinos) which come out from a black hole can own negative energy values? 
Can you give a definitive answer, as yes or no, with reasons ?

d- Is it possible to ask if dark energy can own negative energy value ? Why ? 
Can you give a definitive answer, as yes or no, with reasons ?

Yours Sincerely
 Birol

Re: Can Dark Energy be Negative ?