Showing posts with label Galileo. Show all posts
Showing posts with label Galileo. Show all posts

Tuesday, May 17, 2016

Day 276: Galileo’S Daughter



Most Illustrious Lord Father,

We are terribly saddened by the death of your cherished sister, our dear aunt; but our sorrow at losing her is as nothing compared to our concern for your sake, because your suffering will be all the greater, Sire, as truly you have no one else left in your world, now that she, who could not have been more precious to you, has departed, and therefore we can only imagine how you sustain the severity of such a sudden and completely unexpected blow. And while I tell you that we share deeply in your grief, you would do well to draw even greater comfort from contemplating the general state of human misery, since we are all of us here on Earth like strangers and wayfarers, who soon will be bound for our true homeland in Heaven, where there is perfect happiness, and where we must hope that your sister’s blessed soul has already gone. Thus, for the love of God, we pray you, Sire, to be consoled and to put yourself in His hands, for, as you know so well, that is what He wants of you; to do otherwise would be to injure yourself and hurt us, too, because we lament grievously when we hear that you are burdened and troubled, as we have no other source of goodness in this world but you.

I will say no more, except that with all our hearts we fervently pray the Lord to comfort you and be with you always, and we greet you dearly with our ardent love.

FROM SAN MATTEO, THE 10TH DAY OF MAY 1623.
Most affectionate daughter,
S. Maria Celeste


The day after his sister Virginia’s funeral, the already world-renowned scientist Galileo Galilei received this, the first of 124 surviving letters from the once-voluminous correspondence he carried on with his elder daughter. She alone of Galileo’s three children mirrored his own brilliance, industry, and sensibility, and by virtue of these qualities became his confidante.

Galileo’s daughter, born of his long illicit liaison with the beautiful Marina Gamba of Venice, entered the world in the summer heat of a new century, on August 13, 1600—the same year the Dominican friar Giordano Bruno was burned at the stake in Rome for insisting, among his many heresies and blasphemies, that the Earth traveled around the Sun, instead of remaining motionless at the center of the universe. In a world that did not yet know its place, Galileo would engage this same cosmic conflict with the Church, treading a dangerous path between the Heaven he revered as a good Catholic and the heavens he revealed through his telescope.

Galileo christened his daughter Virginia, in honor of his “cherished sister.” But because he never married Virginia’s mother, he deemed the girl herself unmarriageable. Soon after her thirteenth birthday, he placed her at the Convent of San Matteo in Arcetri, where she lived out her life in poverty and seclusion.

Virginia adopted the name Maria Celeste when she became a nun, in a gesture that acknowledged her father’s fascination with the stars. Even after she professed a life of prayer and penance, she remained devoted to Galileo as though to a patron saint. The doting concern evident in her condolence letter was only to intensify over the ensuing decade as her father grew old, fell more frequently ill, pursued his singular research nevertheless, and published a book that brought him to trial by the Holy Office of the Inquisition.

The “we” of Suor Maria Celeste’s letter speaks for herself and her sister, Livia—Galileo’s strange, silent second daughter, who also took the veil and vows at San Matteo to become Suor Arcangela. Meanwhile their brother, Vincenzio, the youngest child of Galileo and Marina’s union, had been legitimized in a fiat by the grand duke of Tuscany and gone off to study law at the University of Pisa.
   
Thus Suor Maria Celeste consoled Galileo for being left alone in his world, with daughters cloistered in the separate world of nuns, his son not yet a man, his former mistress dead, his family of origin all deceased or dispersed.

Galileo, now fifty-nine, also stood boldly alone in his world-view, as Suor Maria Celeste knew from reading the books he wrote and the letters he shared with her from colleagues and critics all over Italy, as well as from across the continent beyond the Alps. Although her father had started his career as a professor of mathematics, teaching first at Pisa and then at Padua, every philosopher in Europe tied Galileo’s name to the most startling series of astronomical discoveries ever claimed by a single individual.

In 1609, when Suor Maria Celeste was still a child in Padua, Galileo had set a telescope in the garden behind his house and turned it skyward. Never-before-seen stars leaped out of the darkness to enhance familiar constellations; the nebulous Milky Way resolved into a swath of densely packed stars; mountains and valleys pockmarked the storied perfection of the Moon; and a retinue of four attendant bodies traveled regularly around Jupiter like a planetary system in miniature.

“I render infinite thanks to God,” Galileo intoned after those nights of wonder, “for being so kind as to make me alone the first observer of marvels kept hidden in obscurity for all previous centuries.”

The newfound worlds transformed Galileo’s life. He won appointment as chief mathematician and philosopher to the grand duke in 1610, and moved to Florence to assume his position at the court of Cosimo de’ Medici. He took along with him his two daughters, then ten and nine years old, but he left Vincenzio, who was only four when greatness descended on the family, to live a while longer in Padua with Marina.

Galileo found himself lionized as another Columbus for his conquests. Even as he attained the height of his glory, however, he attracted enmity and suspicion. For instead of opening a distant land dominated by heathens, Galileo trespassed on holy ground. Hardly had his first spate of findings stunned the populace of Europe before a new wave followed: He saw dark spots creeping continuously across the face of the Sun, and “the mother of loves,” as he called the planet Venus, cycling through phases from full to crescent, just as the Moon did.
All his observations lent credence to the unpopular Sun-centered universe of Nicolaus Copernicus, which had been introduced over half a century previously, but foundered on lack of evidence.

Galileo’s efforts provided the beginning of a proof. And his flamboyant style of promulgating his ideas—sometimes in bawdy humorous writings, sometimes loudly at dinner parties and staged debates—transported the new astronomy from the Latin Quarters of the universities into the public arena. In 1616, a pope and a cardinal inquisitor reprimanded Galileo, warning him to curtail his forays into the supernal realms. The motions of the heavenly bodies, they said, having been touched upon in the Psalms, the Book of Joshua, and elsewhere in the Bible, were matters best left to the Holy Fathers of the Church.

Galileo obeyed their orders, silencing himself on the subject. For seven cautious years he turned his efforts to less perilous pursuits, such as harnessing his Jovian satellites in the service of navigation, to help sailors discover their longitude at sea. He studied poetry and wrote literary criticism. Modifying his telescope, he developed a compound microscope. “I have observed many tiny animals with great admiration,” he reported, “among which the flea is quite horrible, the gnat and the moth very beautiful; and with great satisfaction I have seen how flies and other little animals can walk attached to mirrors, upside down.”

Shortly after his sister’s death in May of 1623, however, Galileo found reason to return to the Sun-centered universe like a moth to a flame. That summer a new pope ascended the throne of Saint Peter in Rome. The Supreme Pontiff Urban VIII brought to the Holy See an intellectualism and an interest in scientific investigation not shared by his immediate predecessors. Galileo knew the man personally—he had demonstrated his telescope to him and the two had taken the same side one night in a debate about floating bodies after a banquet at the Florentine court. Urban, for his part, had admired Galileo so long and well that he had even written a poem for him, mentioning the sights revealed by “Galileo’s glass.”

The presence of the poet pope encouraged Galileo to proceed with a long-planned popular dissertation on the two rival theories of cosmology: the Sun-centered and the Earth-centered, or, in his words, the “two chief systems of the world.”

It might have been difficult for Suor Maria Celeste to condone this course—to reconcile her role as a bride of Christ with her father’s position as potentially the greatest enemy of the Catholic Church since Martin Luther. But instead she approved of his endeavors because she knew the depth of his faith. She accepted Galileo’s conviction that God had dictated the Holy Scriptures to guide men’s spirits but proffered the unraveling of the universe as a challenge to their intelligence. Understanding her father’s prodigious capacity in this pursuit, she prayed for his health, for his longevity, for the fulfillment of his “every just desire.” As the convent’s apothecary, she concocted elixirs and pills to strengthen him for his studies and protect him from epidemic diseases. Her letters, animated by her belief in Galileo’s innocence of any heretical depravity, carried him through the ordeal of his ultimate confrontation with Urban and the Inquisition in 1633.

No detectable strife ever disturbed the affectionate relationship between Galileo and his daughter. Theirs is not a tale of abuse or rejection or intentional stifling of abilities. Rather, it is a love story, a tragedy, and a mystery.

~~Galileo’S Daughter- A Historical Memoir of Science, faith, and love  -by- Dava Sobel

Tuesday, September 29, 2015

Day 46 : Book Excerpt : Making Starships and Stargates

Ernst Mach, an Austrian physicist of the late nineteenth and early twentieth centuries, is now chiefly known for Mach “numbers” (think Mustang Mach One, or the Mach 3, SR71 Blackbird). But during his lifetime, Mach was best known for penetrating critiques of the foundations of physics. In the 1880s he published a book – The Science of Mechanics – where he took Newton to task for a number of things that had come to be casually accepted about the foundations of mechanics – in particular, Newton’s notions of absolute space and time, and the nature of inertia, that property of real objects that causes them to resist changes in their states of motion.

Einstein, as a youngster, had read Mach’s works, and it is widely believed that Mach’s critiques of “classical,” that is, pre-quantum mechanical, physics deeply influenced him in his construction of his theories of relativity. Indeed, Einstein, before he became famous, had visited Mach in Vienna, intent on trying to convince Mach that atoms were real. (The work Einstein had done on Brownian motion, a random microscopic motion of very small particles, to get his doctoral degree had demonstrated the fact that matter was atomic). Mach had been cordial, but the young Einstein had not changed Mach’s mind.

Nonetheless, it was Mach’s critiques of space, time, and matter that had the most profound effect on Einstein. And shortly after the publication of his earliest papers on General Relativity Theory (GRT) in late 1915 and early 1916, Einstein argued that, in his words, Mach’s principle should be an explicit property of GRT. Einstein defined Mach’s principle as the “relativity of inertia,” that is, the inertial properties of material objects should depend on the presence and action of other material objects in the surrounding spacetime, and ultimately, the entire universe. Framing the principle this way, Einstein found it impossible to show that Mach’s principle was a fundamental feature of GRT. But Einstein’s insight started arguments about the “origin of inertia” that continue to this day. Those arguments can only be understood in the context of Einstein’s theories of relativity, as inertia is an implicit feature of those theories (and indeed of any theory of mechanics). Since the issue of the origin of inertia is not the customary focus of examinations of the theories of relativity, we now turn briefly to those theories with the origin of inertia as our chief concern.

Einstein had two key insights that led to his theories of relativity. The first was that if there really is no preferred reference frame – as is suggested by electrodynamics – it must be the case that when you measure the speed of light in vacuum, you always get the same number, no matter how you are moving with respect to the source of the light. When the implications of this fact for our understanding of time are appreciated, this leads to Special Relativity Theory (SRT), in turn, leads to a connection between energy and inertia that was hitherto unappreciated. The curious behavior of light in SRT is normally referred to as the speed of light being a “constant.” That is, whenever anyone measures the speed of light, no matter who, where, or when they are, they always get the same number – in centimeter-gram-second (cgs) units, 3 10 10 cm/s. Although this works for SRT, when we get to General Relativity Theory (GRT) we will find this isn’t quite right. But first we should explore some of the elementary features of SRT, as we will need them later. We leave detailed consideration of Einstein’s second key insight – the Equivalence Principle – to the following section, where we examine some of the features of general relativity theory.

Mention relativity, and the name that immediately jumps to mind is Einstein. And in your mental timescape, the turn of the twentieth century suffuses the imagery of your mind’s eye. The principle of relativity, however, is much older than Einstein. In fact, it was first articulated and argued for by Galileo Galilei in the early seventeenth century. A dedicated advocate of Copernican heliocentric astronomy, Galileo was determined to replace Aristotelian physics, which undergirded the prevailing Ptolemaic geocentric astronomy of his day, with new notions about mechanics. Galileo hoped, by showing that Aristotelian ideas on mechanics were wrong, to undercut the substructure of geocentric astronomy. Did Galileo change any of his contemporaries’ minds? Probably not. Once people think they’ve got something figured out, it’s almost impossible to get them to change their minds. As Max Planck remarked when asked if his contemporaries had adopted his ideas on quantum theory (of which Planck was the founder), people don’t change their minds – they die. But Galileo did succeed in influencing the younger generation of his day.


~~Making Starships and Stargates- The Science of Interstellar Transport and Absurdly Benign Wormholes -by- James F. Woodward