مقدمہ
اْردو زبان و ادب کے طلبہ اور اساتذہ کے لیے ایک خوب صورت علمی تحفہ
ڈاکٹر عظیم اللہ جندران
میں سوچتا ہوں کہ اس گلستاں میں ہوسکے تو گلاب اْگائیں
وہ جس کا حرف حرف آگہی ہو، ورق ورق وہ کتاب اْگائیں
(پروفیسر اسلم انصاری)
درخت اپنے پھل سے پہچانا جاتا ہے۔اْستاد کی پہچان اس کے شاگرد ہوتے ہیں۔ عزیزم محترم نعمت اللہ ارشد گھمن راقم السطور کے شاگردانِ رشید میں شامل ہیں۔ موصوف کا شمار میرے نہایت مودب،مہذب ، ملنسار اور ممتاز شاگردوں میں ہوتا ہے۔ ماشاء اللہ تعالی! الحمدللہ!
یہ امر باعث مسرت ہے نعمت اللہ ارشد گھمن صاحب اپنے سروس کیریئر میں بفضل تعالیٰ جل جلالہ بطفیل مصطفیٰﷺ بتدریج ارتقائی مراحل کی طرف رواں دواں ہیں۔ شعبہ تعلیم میں معلم اور متعلم کے منصب پر فائز رہتے ہوئے جناب ِ گھمن اب مصنف، مولف، مرتب اور محقق کی پیشہ ورانہ جہات کی طرف قدم اٹھا رہے ہیں۔ بقول فاروق امیر:
نئی راہوں کو ہم نے کھوجنا ہے
نئے منظر، نظارے سوجھتے ہیں!
’’ مباحث:‘‘ محترم گھمن صاحب کی تازہ تصنیف و تالیف ہے۔ اس کتاب کا انتساب دو اساتذہ کرام کے نام ہے۔ کتاب کا اولین انتساب جس شخصیت کے نام ہے وہ مصنف و مولف کی والدہ محترمہ ہیں۔والدہ محترمہ کی گود ہر انسان کے لیے اولین درس گاہ ہے۔ پہلی دانش گاہ ہر ذی شعور کے لیے ماں کی گود ہی ہوتی ہے۔ انتساب میں دوسرا نام محترم'ڈاکتر فرتاش سید مرحوم" کا ہے۔
Teacher is the gaeway to the world of knoldge whatever be the level school, university or college(S.U. Jundran)
انتساب کے لیے یہ انتخاب اور انداز واقعی لائق تحسین اور لاجواب ہے۔ قابلِ تقلید بھی ہے۔
کتاب کا بنیادی موضوع" مباحث" ہے۔ یہ مباحث مندرجہ ذیل ابواب پر مشتمل ہیں:
تحقیق کے مباحث لسانیات کے مباحث تنقید کے مباحث...
Benazir Bhutto happened to be the first constitutionally chosen female leader of any Muslim country in Modern times. She ascended to office amid the legacy of General Zia-ul-Haq’s regime and civil-military bureaucracy that prompted diverse deterrence for her governments and abstained her from the application of her constitutional power. The essence of challenges was mostly political, but the grounds that created these abysses were political and gender partiality. Based on the above discourse, this article attempts to underline the torments confronted by Benazir being the new chapter in our political society. This is the empirical account of Benazir’s twin governments grounded on the views of important politicians who sight and accompanied her in her journey of power. To ponder the reasons that refrained Benazir from having true legal authority the study is divided into the following parts: (1) Challenge and response encountered by Benazir in the first tenure of her Prime Ministership (1988-90), (2) Challenge and response encountered by Benazir in the second tenure of her Prime Ministership (1993-1996). The PPP government had made some new political strides in general, but it was persistently controlled by the army. In the first government, the brass leadership and opposition and in later government civil-military bureaucracy and opposition impaired the democratic traditions. However, amid all this Benazir succeeded to do some pragmatic politics and defying the anti-PPP mindset.
In this thesis, we have studied the propagation of nonlinear electrostatic waves in a nonMaxwellian plasma in which electrons follow the generalized (??,??) distribution function which has the advantage that it mimics most of the distribution functions observed in space plasmas. Generally spectral index ?? corresponds to the flatness and ?? corresponds to the high energy tail in the profile of the distribution. The generalized (??,??) distribution function is the generalized form of kappa and Maxwellian distribution function and can be reduced to these in the limits ??=0,??=(??+1) and ??=0,??→∞, respectively. First we studied the propagation of nonlinear ion acoustic waves in a (??,??) distributed plasma and derived the Korteweg-de Vries (KdV) equation. In the past, KdV equation has been derived for ion acoustic waves with Boltzmannian or kappa distributed electrons and only compressive solitary structures were obtained. We have shown that when electrons are modelled by (??,??) distribution, the nonlinear ion acoustic waves admit both humps and dips in the perturbed potential. We found that for positive values of ??, which correspond to flat-topped distribution, the nonlinear ion acoustic waves admit compressive solitary structures or density humps. And for negative values of ??, which correspond to a spiky distribution, the nonlinear ion acoustic waves admit rarefactive solitary structures or density depletions. It has also been shown that the generalized (??,??) distribution function provides another way to explicate the density depletions observed by Freja and Viking satellites previously explained by proposing Cairns distribution function. In the third chapter, we have studied the propagation of nonlinear electron acoustic waves (EAWs) by deriving the KdV equation in a plasma comprising of cold and hot electron populations in which the ions form the neutralizing background. The hot electrons have been assumed to follow the generalized (??,??) distribution. Interestingly, it has been found that unlike Maxwellian and kappa distributions, the electron acoustic waves admit not only rarefactive structures but also allow the formation of compressive solitary structures for generalized (??,??) distribution. Using the plasma parameters, typically found in the Saturn’s magnetosphere and the Earth’s auroral region, where two x populations of electrons and electron acoustic solitary waves have been observed, we have given an estimate of the scale lengths over which these nonlinear waves are expected to form and how the size of these structures would vary with the change in the shape of the distribution function and with the change of the plasma parameters. In chapter-4, we then derived the modified Korteweg-de Vries (mKdV) equation to study nonlinear ion acoustic waves in a plasma in which electrons follow generalized (??,??) distribution. The spectral index ?? in the distribution corresponds to the flat top at low energy and by increasing its value flat top in the distribution increases. The spectral index ?? can also have negative values due to which distribution becomes spiky at low energies. Such flat topped or spiky distributions have been frequently observed in space plasmas. By employing (??,??) distribution, it has been shown that solitary structures are much influenced by the spectral index ??. This study highlighted the effect of low energy particles on the propagation characteristics of the solitary structures which could not be done by employing Maxwellian or kappa distributions and be helpful in explaining the underline physics in those regions where such flat top distributions are observed. In the chapter 5, we have studied the propagation of nonlinear ion acoustic shock waves in unmagnetized and collisionless plasma in the presence of electrons that follow the generalized (??,??) distribution. The Burger and Korteweg-de Vries–Burger (KdV-Burger) equations have been derived through reductive perturbation technique and via tangent hyperbolic method shock like solutions have been presented analytically for both Burger and KdV-Burger equations. It has been found that the strength and steepness of shock waves are affected by the flatness parameter ??, tail parameter ?? and the nonlinear propagation velocity ??. It is found that the shock strength of KdV–Burger is less than simple Burger equation’s shock. We concluded that propagation of nonlinear electrostatic waves strongly dependent on the profile of the distribution function and the results obtained are of great importance as they interpret those observations which could not be predicted on the basis of Maxwellian or kappa distribution functions.