Archive for July, 2009

General Relativity (Gravity) and Quantum Theory

July 14, 2009

Modified Newtonian Dynamics by Dr. Sabbir Rahman

Famously, Einstein’s theory of gravity and general relativity (GR) is incompatible with quantum theory (QT), but both are theories that have been experimentally tested to be true to a very high degree of precision, within their own domains.  Reconciling GR and QT is one of the major unsolved problems in contemporary physics.  Here is a fascinating paper by Dr. Sabbir Rahman that outlines a possible solution to the problem.

ABSTRACT

We consider a simple model of the physical vacuum as a self-gravitating rela-
tivistic fluid. Proceeding in a step-by-step manner, we are able to show that the
equations of classical electrodynamics follow if the electromagnetic four-potential
is associated with the four-momentum of a space-filling fluid of neutral spinors
which we identify with neutrinos and antineutrinos. Charged particles, which
we identify with electrons and positrons, act as sinks for the fluid and have
the structure of the maximal fast Kerr solution. Electromagnetic waves are de-
scribed by oscillations in the fluid and interactions between charges occur via the
exchange of photons, which have the structure of entwined neutrino-antineutrino
pairs that form twisted closed loops in spacetime connecting the charges. The
model predicts that antimatter has negative mass, and that neutrinos are matter-
antimatter dipoles. Together these suffice to explain the presence of modified
Newtonian dynamics as a gravitational polarisation effect.

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The Moonsighting Controversy: Can Eid al-Adha be separated from the Hajj?

July 14, 2009

Is Eid-ul-Adha connected with the Hajj

In past years, the Saudi announcements for the dates of Eid have been heavily criticised by Muslim astronomers.  Many scholars argue that Muslims around the world are not obliged to celebrate Eid al-Adha the day after the Day of Arafat during the Hajj in present-day Saudi Arabia.  This 10-page article by Hood Bradford discusses the issue, with useful quotes from classical and contemporary jurists.

CONTENTS

1. DETERMINING THE ISLAMIC CALENDAR: GLOBAL VS. REGIONAL SIGHTING
2. DETERMINING THE ISLAMIC CALENDAR: USING ASTRONOMY AND CALCULATIONS
3. EVIDENCE FOR ARAFAH BEING THE DAY THE PEOPLE STAND AT ARAFAH AND EID AL ADHAA COINCIDING WITH THE STONING OF THE JAMARAAT
4. PRAYING WITH THE REST OF THE MUSLIMS IN THE COMMUNITY
5. RUDENESS AND SPEAKING BAD OF OTHERS FOR FOLLOWING AN ISSUE WHICH THERE IS LEGITMATE DIFFERENCE OF OPINION

Ibn Taymiyyah on Fasting and Moonsighting

July 14, 2009

Ibn Taymiyyah – Fasting and Moonsighting v1 (16 pages including commentary by Usama Hasan)

From the Collected Fatwas of Ibn Taymiyyah (Majmu’ Fatawa Shaykh al-Islam Ibn Taymiyyah), ed. ‘Abd al-Rahman b. Qasim and his son Muhammad, Riyadh, 1398 H, vol. 25 (vol. 5 of the Fiqh Section), pp. 98-113.

TABLE OF CONTENTS

1 Fasting on the day when it might or might not be the first of Ramadan
1.1 Caution in legal matters
1.2 Does the hilal exist only when it is visible, or does it have an independent existence?

2 How far geographically is a hilal-sighting valid?

2.1 The impact of knowledge and communication constraints on this matter
2.2 Travelling to a place where Ramadan began on a different day
2.3 The importance of information in this matter
2.4 The meaning of “hilal”
2.5 Summary of the discussion so far
2.6 A further discussion about the hilal and the Hajj

Unity of Knowledge

July 14, 2009

A 1-slide “tree of knowledge” by Dr. Sabbir Rahman

Unity of Knowledge

An Introduction to the Moonsighting Controversy

July 14, 2009

Introduction to Moonsighting Controversy

A good 10-page summary of the main issues, by Rukhsana Begum.