Hairs on the cosmological horizon
نویسندگان
چکیده
We investigate the possibility of having hairs on the cosmological horizon. The cosmological horizon shares similar properties of black hole horizons in the aspect of having hairs on the horizon. For those theories admitting haired black hole solutions, the nontrivial matter fields may reach the cosmological horizon and then extend beyond a universal critical point satisfying r > 3m(r), where m(r) is a mass function in the metric. For Q-stars and boson stars, the matter fields cannot reach the cosmological horizon. We also investigate the effects of presence of a cosmological constant on the no short hair conjecture and no scalar hair theorem of black holes. By using the Bekenstein’s identity method, one can prove the no scalar hair theorem for Electronic address: [email protected] Electronic address: [email protected] Electronic address: [email protected]
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